[X-Ray Field Unit Generator Item 9606000]
[From the U.S. Government Publishing Office, www.gpo.gov]

Document . MS’S® WAR DEPARTMENT TECHNICAL MANUAL
NON-CIRCULATING
X-RAY FIELD
UNIT GENERATOR
ITEM 9606000
WAR DEPARTMENT • NOVEMBER 1944

WAR DEPARTMENT TECHNICAL MANUAL
T M 8-630
X-RAY FIELD UNIT
GENERATOR
ITEM 9606000
WAR DEPARTMENT • NOVEMBER 19 4 4
United States Government Printing Office, Washington: 1944
For sale hy the Superintendent of Documents, U. S. Government
Printing Office, Washington 25, D. C.
WAR DEPARTMENT,
Washington 25, D. C., 30 November, 1944.
TM 8—630, X-ray Field Unit Generator, Item 9606000, is published for
the information and guidance of all concerned.
[AG 300.7 (18 Oct 44).]
By order of the Secretary of War:
G. C. MARSHALL,
Chief of Staff.
Official:
J. A. ULIO,
Major General,
The Adjutant General.
Distribution:
Armies (2) ; Corps (2) ; Depts (10) ; Sv C (5) ; ID 8 (4) ; IR 8 (1) ;
IR 8 (3) (2) (1); IC 8 (2; Base C (5); Numbered Air Forces
(5); Med Deps, Continental (25) except St. Louis Med Dep (50),
Med Sec ASF Dep (10), T of Opn (10) ; PE (2) Med Sec, ASF
Dep (10).
ID 8: T/O & E 8-550.
IB 8: T/O & E 8-611; 8-610.
IR 8 (3): T/O & E 8-581; 8-580, Evac Hosps.
IR 8 (2): T/O &E 8-560, 8-510; 8-590; 8-572S.
IR 8 (1) : T/O & E 8—580, Conval Hosps.
IC 8: T/O & E 8-187, 8-667.
For explanation of symbols, see FM 21-6.
H
CONTENTS
Paragraph Page
PART ONE. INTRODUCTION.
Section I. General.
Scope ..................................................................................... 1 1
i Records ................................................................................. 2 1
II. Description and data.
Description .................................................................... 3 1
Tabulated data ..................................... 4 - 8
III. Tools, parts, and accessories.
Tools ................ ,............................... 5 8
Parts ............................... 6 8
Accessories ........................................ 7 8
PART TWO . OPERATING INSTRUCTIONS.
Section IV. General.
Scope..................... 8 9
V. Service upon receipt of equipment.
New equipment ..................... 9 9
Used equipment .................... 10 11
VI. Controls and instruments.
Controls ............................................................................... 11 11
Instruments ... .................................................. 12 11
VII. Operation under usual conditions.
Scope ..................................................................................... 13 11
Starting engine ............. 14 11
Engine warm-up ......................................... 15 12
Connecting X-ray machine ............................................... 16 12
Stopping engine ........................._....................................... 17 12
VIII. Operation of auxiliary equipment.
General .............:................................................................... 18 12
IX. Operation under unusual conditions.
Scope ................................................................. 19 12
Extreme cold ......................... 20 13
Extreme heat .... 21 13
Dust and sand ....................... 22 13
X. Demolition to prevent enemy use.
Demolition ................................................. 23 13
PART THR EE. MAINTENANCE INSTRUCTIONS.
Section XI. General.
Scope.................... >......................... 24 14
XII. Special organizational tools and equipment.
General :............................................................................. 25 14
XIII. Lubrication.
Lubrication ................................................................. 26 15
III
Paragraph Pagt
XIV. Preventive maintenance services.
General .................................................................... 27 15
Operators service (first echelon) ______ 28 15
Before operation services ................................................... 29 16
During operation services ........................ 30 16
At stop services ............................... 31 17
After operation services................................. 32 17
Second echelon preventive maintenance ______ 33 19
XV. Trouble shooting.
General .................................. 34 23
Engine................................................................................... 35 23
Generator ................................................................ 36 26
XVI. Ignition system service.
General ..............................„. 37 26
Ignition breaker assembly ........................ 38 27
Spark plug cables............................................... 39 30
Magneto and ignition breaker test .... 40 30
Magneto condenser ............................................ 41 30
Spark plugs ..... _....................................... 42 30
XVII. Fuel supply system service.
General ............................................ ‘...... 43 31
Fuel tank and fittings ........... 44 32
Fuel pump ................................................................. 45 34
Fuel supply system test ...... 46 34
XVIII. Air cleaner assembly and carburetor service.
General .... ................. ........... '.......... _....... 47 35
Air cleaner..............?........................ ......................:......... 48 35
Breather tube screen ................................ 49 35
Carburetor ......................... 50 36
XIX. Cylinder heads and valve mechanism Service.
General ................ 51 36
Removing carbon and adjusting valve tappets ............... 52 36
Compression test....................................... 53 40
XX. Generator service.
General ...................................... ;.................. 54 40
Brushes, brush springs, and ball bearing ...................... 55 41
PART FOU R. AUXILIARY EQUIPMENT.
Section XXI. General.
Scope.......................................................... 56 46
PART FIVE. REPAIR INSTRUCTIONS.
Section XXII. General.
Scope........................................................ 57 47
XXIII. Carburetor repair.
General . ............. •..... _...... 58 47
Removing and disassembling ... ......................................... 59 47
Cleaning and replacing parts .............................. _............. 60 49
Reassembling and installing................. _............. 61 49
Adjusting and testing .............................. ..... 62 52
IV
Paragraph Page
XXIV- Fuel pump repair.
General ............ 63 52
Removing and disassembling ...... 64 55
Cleaning, inspecting, and replacing parts ...................... 65 55
Reassembling and installing ............................................. 66 56
Adjusting and testing ........................................................ 67 57
XXV. Magneto repair.
General ....■...................... 68 57
Removing and disassembling ...............................'............. 69 57
Cleaning, testing, inspecting, and replacing parts ......... 70 58
Reassembling and installing .......................................... 71 58
Adjusting and testing ........... .. ..........!.......................... ....'...:........... 72 60
XXVI. Governor and booster repair.
General ............... 73 61
Removing and disassembling .................... 74 61
Cleaning, inspecting, replacing, and lubricating parts..... 75 67
Reassembling and installing...... ...................... 76 68
Adjusting and testing .......... 77 69
XXVII. Cylinder and crankcase mechanism repair.
General ................................................................................. 78 71
Removing external parts and assemblies ....... 79 71
Disassembling ........... 80 72
Servicing oil pump on model OTC—38 .......................... 81 77
Servicing oil pump on model OTC—38B ........................ 82 79
Cleaning and inspecting cylinder heads ........................ 83 80
Cleaning and inspecting cylinders ................... 84 80
Cleaning and inspecting crankcase ................ 85 81
Cleaning and inspecting oil base ................... 86 81
Cleaning and inspecting pistons ..... 87 81
Cleaning and inspecting connecting rods .................... 88 82
Cleaning and inspecting crankshaft ................................. 89 82
Cleaning and inspecting camshaft ................................... 90 82
Cleaning and inspecting valves ...................................:....... 91 82
Grinding valves '...................... 92 83
Reassembling ........................... 93 83
Installing engine assemblies ........ 94 87
Running test, adjusting, and tightening ......... ,............... 95 88
XXVIII. Generator repairs.
General ...................,.......................... _.....,................ 96 88
Disassembling ...................................................................... 97 88
Cleaning ...... :.................................................. 98 89
Inspecting brushes, brush springs, and ball bearing......... 99 89
Inspecting commutator and slip rings ...............................100 89
Testing armature and field coils .....................................101 89
Undercutting commutator ............................ 102 91
Reassembling ....................................... 103 91
Testing generator output ........................... 104 y2
V
Paragraph Page
APPENDIX.
Section I. Shipment and storage.
General ............................ 1 93
Preparation for temporary storage and domestic shipment 2 93
II. References.
Army Regulations ............................. 3 94
Field and Technical Manuals .......................................-... 4 94
Army Service Forces Medical Supply Catalog.................. 5 94
List of forms mentioned in manual ;............................... 6 94
List of abbreviations used in manual ............................ 7 94
III. List of all service parts.
Interchangeable service parts ................................... 8 95
Service parts for model OTC—38 only ............................ 9 99
Service parts for model OTC—38B only ........................... 10 109
INDEX .................................................................................................................................. Ill
vi
TM 8-630
1-3
PART ONE
INTRODUCTION
Section I. GENERAL
I. SCOPE, a. These instructions are published for the information and
guidance of the personnel to whom this equipment is assigned. They contain
information on the operation and maintenance of the equipment as well as
descriptions of the major units and their functions in relation to the other
components of the equipment. They apply only to the Medical Department
Item No. 9606000, X-ray field unit generator, and are arranged in five parts:
Part One—Introduction; Part Two—Operating instructions; Part Three—
Maintenance instructions; Part Four-—Auxiliary equipment; Part Five—Repair
instructions.
b. Supply Catalogs, Field Manuals, Technical Manuals, and other publications
applicable to the material covered by this manual are listed in reference
section at end of manual.
2. RECORDS. AR 850—15 and current directives direct that WD, Form 48,
Drivers Trip Ticket and Preventive Maintenance Service Record and WD,
AGO Form 461, Work Sheet for Wheeled and Half-track Vehicles, or an
adapted form of each be used to record the various preventive maintenance
services performed.
Section II. DESCRIPTION AND DATA
3. DESCRIPTION, a. General information. The X-ray field unit generator
is a self-contained unit completely inclosed in a carrying case. The item is
a gasoline engine powered electrical generator designed to furnish sufficient
electrical energy of the proper wave form to operate Medical Department items
No. 9608508 and No. 9608510 X-ray field unit machines, and 9621500 X-ray
field unit, fluoroscopic and foreign body localization.
b. Identification information. The carrying case is marked with Medical
Department item No. 9606000. If the plant is separated from the carrying
case, it can be identified by the manufacturers nameplate on the blower housing
showing the model No. OTC-38 or OTC-38B. A similar unit showing
model No. OTC-1 is not to be confused with the X-ray field unit generator.
c. Models. At present two models, OTC—38 and OTC—38B, are supplied
under Medical Department item No. 9606000. The electrical output of both
models is identical. External appearance is very similar. The construction
of the models varies in two main respects. Model OTC-38 has a plunger type
oil pump with oil lines to the front and rear crankshaft bearings whereas model
OTC—38B has a gear type oil pump and a crankcase with drilled oil passages.
Instructions contained in this manual apply to either model unless one model
is specifically stated at beginning of section, paragraph, or subparagraph.
I
TM 8-630
3 X-RAY FIELD UNIT GENERATOR
T %. —(13)
(Q • 7^
(t)\ ®
T""7 .............. ''^Tl 17
vb—19-^7x77^
■ —...................................... ...
CD*
( // *®
® @® ® ® /Z
Figure 1. Carrying case assembly.
2
TM 8-630
3
INTRODUCTION
Med.
Dept. No. Nomenclature
Med.
Dept. No. Nomenclature
1. 9R009I2 Panel, base and skid. 12. 9R00906 Panel, top, cable compart2.
9R00898 Bracket, clamp. ment.
3. SR00685 Nut, 5/16 x 18, wing» 13. 9R009I8 Handle, box, tool and
4. 9R00892 Panel, left side.
spare part.
14. 9R00908 Panel, back.
5. 9R009I0 Panel, front. 15. 9R00894 Panel, right side.
6. 9R00890 Handle, carrying. 16. 9R008I0 Rod, grounding.
7. 9R00902 Snap and chain, harness. 17. 9R00812 Cable, grounding.
8. 9R00900 Clasp, trunk. 18. 9R00820 Clip, spring.
9. 9R00896 Box, tool and spare part. 19. 9R008I8 Plug, angle-cord.
10. 9R009I6 Handle, cover, wire com20.
9R008I6 Connector, angle-cord.
partment. 21. 9R008I4 Cable, No. 12, type S,
II. 9R00904 Cover, wire compartment. 3 conductor.
Figure 1. Carrying case assembly—Continued.
3
TM 8-630
3
X-RAY FIELD UNIT GENERATOR
| . bQ QI jra
w IB 00 / O
■h @)
i ill (^)
wf (tW ®— ®^>©
©—— N ’. ®^\
(AJ I I ®C^L_,
©_____ i____
©^—c ^®=
z~x I IP---- (20) /h QV^i* | [ | 5
Ifl ®“*L 1
®k |
on M : Mi 1
....
Figure 2. Tools with X-ray field unit generator.
4
8-630
3
INTRODUCTION
TM
Med.
Dept. No. Nomenclature
1. TR02057 Wrench, double end, thin
head, 15 degree, % inch
x 11/16 inch.
2. TR02054 Wrench, double end, engineer,
15 degree, 9/16 inch
x % inch.
3. TR02048 Wrench, double end, engineer,
15 degree, 7/16 inch
x */? inch.
4. TR02045 Wrench, double end, engineer,
15 degree, % inch
x 7/16 inch.
5. TR0I355 File, ignition point.
6. TR02080 Wrench, ignition point, for
nut screw sizes.
7. TR0I7I0 Screwdriver, normal duty,
inch shank, 6 inch blade
length.
8. TR0I705 Screwdriver, normal duty,
*/4 inch shank, 4 inch blade
length.
9. TR0I033 Bush, wire, 14 inch handle.
10. TR023I5 Handle, socket wrench, bar
type, 9/16 inch dia., 10 inch
length.
II. TR02255 Adapter, socket wrench,
1/2 inch female square
drive, 9/16 inch round
handle hole.
Med.
Dept. No. Nomenclature
12. TR02355 Plug-connector, socket
wrench, /a inch square
drive, I1/, inch length.
Socket, 7/16 inch 12 point
opening, 92 inch square
13. TR02425
drive.
14. TR02428 Socket, I/2 inch 12 point
opening, */2 inch square
drive.
15. TR0243I Socket, 9/16 inch 12 point
opening, ^2 inch square
drive.
16. TR0I9I5 Wrench, setscrew, Allen,
No. 10.
17. TR0I9I8 Wrench, setscrew, Allen,
*4 inch.
18. TRO 1921 Wrench, setscrew, Allen,
5/16 inch.
19. TRO 1924 Wrench, setscrew, Allen,
% inch.
20. TRO 1865 Wrench, adjustable, auto
type, 8/2 inch length, 2%
inch opening.
21. TR0I6I0 Plier, slip joint, shear cutting,
6 inch.
22. TR0I430 Gage, feeler, .001 inch to
.025 inch.
23. TR022I5 Wrench, spark plug, 27/32
inch x 1 — 1/32 inches: with
handle, TR023I0.
Figure 2. Tools with X-ray field unit generator—Continued.
5
TM 8-630
3 X-RAY FIELD UNIT GENERATOR
5)4 ®t ® ®@^
......... (5 J ilk (12s) v—<< ORmk kJ!/
■' ® ‘’’•A @(o
©—i J£°
} ® ® ~ ; ■
®,__t * t" s""' I®* a
fr--------<7) t^yQ \>Q J ' |
Med.
Dept. No. Nomenclature Quantity
9. 9R00648 Gasket, manifold. 8
10. 9R00832 Gasket, shut-off
screw. 4
II. 9R00628 Gasket, valve cover. 4
12. 9R00744 Line, fuel, carburetor.
I
13. 9R00746 Line, fuel, tank. I
14. 9R00780 Plug, spark: with
gasket. 4
15. 9R00826 Rope, starter. 2
16. 9R00800 Spring, brush, AC. 4
17. 9R00794 Spring, brush, DC. 4
Med.
Dept. No. Nomenclature Quantity
9R00772 Arm and points,
breaker. 1
9R00798 Brush, AC. 4
9R00788 Brush, DC. 4
9R00766
9R00804
9R006I2
Condenser, magneto 1
Gasket, bearing
cover. 2
Gasket, Cylinder
head , 4
9R00830
9R00756
Gasket, filler cap. 2
Gasket, fuel pump,
bowl. 2
i.
2.
3.
4.
5.
6.
7.
8.
Figure 3. Spare parts with X-ray field unit generator.
6
TM 8-630
INTRODUCTION 3
' W41
v/CJ"\
x;' ’§’’ | Jf «gr»^' __ z—
® „®
\ ■ I
u ^w JL
X> " ■"* >«„ V:.\ .;*_ .J.I• *—-.- ----------- \V “_ X)
) w J)
Med.
Dept. No. Nomenclature Quantity
I. 9R00754 Bowl, fuel pump. I
2. 9R008I2 Cable, grounding. I
3. 9R00734 Cleaner, air. I
4. 9R00820 Clip, spring. I
5. 9R00738 Gasket, air cleaner. 4
6. 9R00822 Receptacle, duplex. I
Figure 4.
Med.
Dept. No. Nomenclature Quantity
7. 9R00736 Screen, breather
tube. I
8. 9R00750 Gasket, fuel pump
adapter and breather
tube. 4
9. 9R00752 Screen, fuel pump. I
10. 9R00776 Spring, breaker. I
Additional spare parts jor second echelon.
7
TM 8-630
3-7
X-RAY FIELD UNIT GENERATOR
d. Manufacturer. At present this item is manufactured for the Medical
Department by D. W. Onan and Sons, Minneapolis, Minnesota.
4. TABULATED DATA. a. General. (1) Engine.
Two cylinder opposed type.
Four-stroke cycle type.
Air cooled.
Bore, 2% inches.
Stroke, 2^ inches.
Compression ratio, 5.9 cubic inches to 1 cubic inch.
(2) Generator.
Four pole, self-excited type.
b. Performance. (1) Engine. Develops 3.7 horsepower at 1800 revolutions
per minute.
(2) Generator. Furnishes 120-volt single phase 60-cycle alternating current.
Develops 2000-watt unity power factors.
c. Capacities. (1) Engine fuel. 2-gallon fuel tank.
(2) Engine oil. 21/2 quarts.
Section III. TOOLS, PARTS, AND ACCESSORIES
5. TOOLS. Tools for use by the operator of the equipment are shipped with
the unit. They are carried in the tool and spare part box (fig. 1, (9) ) within
the cable compartment top panel. (See fig. 1, (12).) The contents of the
tool box are illustrated and listed in figure 2.
6. PARTS, a. Spare parts with unit. Certain spare parts for replacement by
the operator of the equipment and the organizational maintenance personnel
are shipped with the unit. They are stowed in the tool and spare part box. The
parts are illustrated and listed in figure 3.
b. Second echelon spare parts. All spare parts with the unit are supplied
for replacement by the maintenance personnel of the using organizations.
The additional spare parts supplied to the using organization are illustrated
and listed in figure 4. The conductor cable (fig. 1, (21)) is also supplied
to the using organization as a spare part.
7. ACCESSORIES, a. Carrying case assembly. (See fig. 1.)
b. Conductor cable, plug (fig. 1, (19)) connector (fig. 1, (20)), and
spring clips (fig. 1, (18)).
c. Grounding rod. (See fig. 1, (16).)
d. Grounding cable. (See fig. 1, (17).)
8
TM 8-630
8-9
PART TWO
OPERATING INSTRUCTIONS
Section IV. GENERAL
8. SCOPE. Part two contains information for the guidance of the personnel
responsible for the operation of this equipment. It contains information on
the operation of the equipment with the description and location of the controls
and instruments.
Section V. SERVICE UPON RECEIPT OF EQUIPMENT
9. NEW EQUIPMENT, a. Unpacking. (1) Remove the packing crate.
(2) Place the cased unit in the location selected.
(3) Remove the cable compartment top panel. (See fig. 1, (12).)
(4) Remove the front panel. (See fig. 1, (5).)
(5) No further unpacking is necessary to put the unit in operation.
b. Assembling. The unit is completely assembled within the carrying
case when shipped. No mechanical assembling of engine or generator is
necessary upon receipt of equipment.
c. Inspecting. (1) Visual. Make a thorough visual inspection for any
apparent damage or shortage.
(2) Running test. Follow procedure for running test contained in items
1 through 14. (See par. 33.) Run the unit for a minimum of 30 minutes.
d. Installing. (1) Location. As this plant is auxiliary to the X-ray field
unit it will frequently be operated in the open. Select a place as free from
sand, mud, or dust as possible. If it can be anticipated that the plant will remain
for some time in one location, it is advisable to build an inclosure about
it. To further protect it from dust or dampness, it should be elevated from
the ground on a platform of convenient height. At all times keep the plant
in an upright level position.
(2) Ventilation. Ventilation is very necessary to prevent serious damage
due to overheating. Any gasoline engine develops heat which must be removed
from the compartment or inclosure in which the engine is operating. Any
inclosure must have sufficient openings or removable panels, depending on
climatic conditions, to permit adequate cooling of this engine.
(3) Exhaust. If the plant is to be used indoors the exhaust gases must
be piped from the building. Use a flexible metal tube not less than 1 inch in
diameter between the exhaust muffler and a solid pipe or vent to the outside.
The flexible tube is necessary to take up the engine vibrations and permit a
leakless connection. A vent pipe with a length of not more than 6 feet will
require a diameter of 1 inch. To prevent any back pressure, an additional
l/2 inch must be added to the vent pipe diameter for each additional 6 feet of
length. Be certain the exhaust vent extends far enough from or above the
building to eliminate the possibility of the exhaust gases being carried back
9
TM 8-630
9
X-RAY FIELD UNIT GENERATOR
I \ I Wf/'S''
(Ti / ///
(vu“'/ k ///>< \(^Vwrv\W?oW0}^ k x / TW f I I ® ® / y
\IlJ \® \W
—@ (21VJ/
(?) 2Z \z>
i ------------ (22)
i.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Med.
Dept. No.
9R05388
9R008I6
9R008I0
9R008I2
9R00892
9R00838
9R00906
9R00869
9R00886
9R00880
Figure 5.
Nomenclature
Cable, line, complete: Assembly;
for X-ray field
unit, machine.
Connector, angle-cord.
Rod, grounding.
Cable, grounding.
Panel, left side.
Pulley, starter rope.
Panel, top, cable compartment.
Outlet, conductor cable.
Petcock, shut-off, fuel tank.
Cap and chain, filler, fuel
tank.
Medical Department Item
Med.
Dept. No. Nomenclature
II. 9R008I8 Plug, angle-cord.
12. Outlet ground terminal.
13. 9R007I9 Control, manual choke.
14. 9R00746 Line, fuel, tank.
15. 9R00754 Bowl, fuel pump.
16. 9R00709 Gage and chain, oil filler.
17. 9R00908 Panel, back.
18. 9R00894 Panel, right side.
19. 9R00763 Button, stop.
20. 9R009I2 Panel, base and skid.
21. 9R008I4 Cable, No. 12, type S, 3
conductor.
22. 9R00820 Clip, spring.
No. 9606000 X-ray field unit generator.
10
TM 8-630
9-14
OPERATING INSTRUCTIONS
into the building. Caution must also be taken to keep the exhaust tube and
vent shielded. During operation the exhaust vent will become extremely hot
and is a fire hazard.
(4) Grounding, (a) Drive grounding rod (fig. 5, (3)) into the earth
for its entire length and near enough to the unit to connect the grounding
cable. (See fig. 5, (4).)
(£) Moisten soil around the grounding rod when in a dry region.
(c) Connect the grounding cable to the grounding rod and on the outlet
ground terminal. (See fig. 5, (12).)
10. USED EQUIPMENT. ■ Procedure for the receipt of used equipment will be
the same as prescribed for new equipment. (See par. 9.) The visual inspection
will be very thorough and a running test (par. 33) of 1 hour will be conducted.
Section VI. CONTROLS AND INSTRUMENTS
I I. CONTROLS, a. Starter. The engine is of the manual crank type using
a starter rope (fig. 3, (15)) and a starter rope pulley. (See fig. 5, (6).)
b. Fuel tank shut-off petcock. The petcock (fig. 5, (9)) is a means of
stopping the flow of gasoline from the fuel tank.
c. Filler cap shut-off screw. The shut-off screw is a part of the fuel tank
filler cap. (See fig. 5, (10).) When closed it seals the fuel tank. When
open it serves as a vacuum break when the fuel is being drained from the
tank.
d. Manual choke control. This control (fig. 5, (13)) is linked to the
choke plate and controls the volume of air entering the carburetor. The operation
of the choke control is the same as on all gasoline engines. Pull out for
starting, push in when running.
e. Stop button. The stop button (fig. 5, 19)), or an identical stop
button in the same position on the opposite side of the unit, is a means of
stopping the engine. Either stop button must be held down until the engine
has completely stopped running.
f. Governor-booster spring adjusting screw. This adjusting screw will
not be changed by the operating personnel.
g. Carburetor idle jet needle. The idle jet needle is held in the factory
adjusted setting by a welded clip. Operating personnel will not change the
existing setting.
12. INSTRUMENTS. The oil filler gauge (fig. 5, (16)) is the only instrument
on the unit.
Section VII. OPERATION UNDER USUAL CONDITIONS
13. SCOPE. This section contains the instructions pertaining to the operation
of a unit which has been serviced upon receipt. (See sec. V.) The operator
will carefully study and apply the instructions for first echelon (operator)
maintenance (par. 28) and lubrication (par. 26).
14. STARTING ENGINE, a. Check the grounding cable (fig. 5, (4)) and
grounding rod (fig. 5, (3)) making certain the connections are firm.
b. Do not connect the generator to the X-ray machine until the engine
is running smoothly.
I I
TM 8-630
14-19
X-RAY FIELD UNIT GENERATOR
c. Open the filler cap shut-off screw in the fuel tank filler cap. (See fig.
5, (10).)
d. Open the fuel tank shut-off petcock. (See fig. 5, (9).)
e. Pull out the manual choke control. (See fig. 5, (13).) In cold climate
it will be necessary to pull the choke control outward for its entire travel.
In hot climates very little movement of the control will be required.
f. Wind the starter rope around the starter rope pulley (fig. 5, (6))
so it will be turned as indicated by the arrow on the pulley.
g. It may be necessary to crank the engine several times before it starts.
15. ENGINE WARM-UP. a. Move the choke control in or out as necessary
to keep the engine running.
b. Continue warm-up period until the choke control has been pushed
inward for its entire travel and the engine runs smoothly. The engine must
not be operated for long periods with the choke control partially pulled out.
16. CONNECTING X-RAY MACHINE, a. Connect the X-ray machine to
the generator by means of the conductor cable. (See fig. 5, (21).) The cable
plug (fig. 5, (11)) and cable outlet (fig. 5, (8)) form a turn lock connection.
Push the plug into the outlet and then turn the plug clockwise.
b. Ground the connection by means of the spring clips (fig. 5, (22))
at the cable connector (fig. 5, (2)) and the cable plug and to the outlet
ground terminal. (See fig. 5, (12).)
c. If there is any unsteadiness of engine operation, or hunting of the
governor after connecting the X-ray machine, the engine is too cold and requires
additional warm-up.
17. STOPPING ENGINE. It is important that this operation be performed
in the follow sequence.
a. Disconnect the X-ray machine from the generator. Turn the cable
plug to the left before pulling from the cable outlet.
b. Press the stop button (fig. 5, (19)), or the identical stop button in
the same position on the opposite side of the machine. The stop button will
ground the ignition circuit and must be depressed until the engine has completely
stopped running.
c. Close the fuel tank shut-off petcock.
Section VIII. OPERATION OF AUXILIARY EQUIPMENT
18. GENERAL. Medical Department item No. 9606000, X-ray field unit
generator, has no auxiliary equipment. Item No. 9606000 is, however, an
auxiliary piece of equipment for Medical Department items No. 9608508 and
No. 9608510, X-ray field unit machines. It may also be used as auxiliary
equipment with item No. 9621500 X-ray field unit, fluoroscopy and foreign
body localization.
Section IX. OPERATION UNDER UNUSUAL CONDITIONS
19. SCOPE. This section covers the exceptions or additions to instructions
for normal operation (sec. VII) that will be necessary for operation under
unusual conditions.
12
TM 8-630
20-23
OPERATING INSTRUCTIONS
20. EXTREME COLD. a. Starting the engine. (1) It would be advisable
to keep the unit indoors or within a heated inclosure when not in operation.
(2) Full outward position of the manual choke control (fig. 5, (13))
will be necessary.
b. Warm-up. Considerably lengthen the warm-up period.
c. Location. Remove only the front panel (fig. 1, (5)) from the carrying
case when the unit is in operation. If possible install unit in a heated
inclosure.
21. EXTREME HEAT. a. Starting. Position of choke control will require very
little movement from the inward running position.
b. Warm-up. Only a relatively short warm-up period will be required.
c. Location. Place unit in an open shaded area and remove all carrying
case panels.
22. DUST AND SAND. a. Reduce operation. Reduce the operating time
of the unit to a minimum.
b. Protect unit. (1) Remove only the front panel of the carrying case,
if temperature is not too high, and place unit with open side downwind.
(2) Close and seal carrying case when unit is not in operation.
Section X. DEMOLITION TO PREVENT ENEMY USE
23. DEMOLITION. Use any means available to render the unit unfit for
enemy use, repair, or salvage. If fire will not disclose your position, puncture
fuel tank, allow time for gasoline to spill over generator, and ignite. Use
sledge or heavy rocks to smash and break off parts, such as, carburetor and
fuel pumps. Should silence and security be necessary in the withdrawal, remove
such parts as the carburetor, spark plugs or fuel pump and bury or
otherwise hide them. If two or more units are with the same organization,
be certain the same parts are removed from each. Because of the small size of
the unit, it may be possible to bury the remaining bulk in an abandoned foxhole
or slit trench.
13
TM 8-630
24-25
PART THREE
MAINTENANCE INSTRUCTIONS
Section XI. GENERAL
24. SCOPE. Part three contains information for the guidance of the personnel
of the using organizations responsible for the maintenance (first and
second echelon) of this equipment. It contains information needed for the
performance of the scheduled lubrication and preventive maintenance services
as well as descriptions of the major systems and units and their functions in
relation to other components of the equipment.
Section XII. SPECIAL ORGANIZATIONAL TOOLS AND EQUIPMENT
25. GENERAL. The tools supplied with the unit (par. 5) are all that are
necessary to perform the maintenance service covered in part three of this
manual. No other tools, special or common, will be required.
No.5001
WAR DEPARTMENT LUBRICATION ORDER
WAR DEPARTMENT WASHINGTON 25, D. C., 26 JULY 1944
GENERATOR, X-RAY FIELD UNIT
ONAN MODELS OTC-38, OTC-38 B For Detailed Instructions, refer to TM 8-630
Clean parts with Solvent, dry cleaning, or Oil, Requisition replacement lubrication Orders from the Reduce intervals under severe operating
fuel, diesel. Dry before lubricating. M"”“* l U“" * conditions
lubricant o Opsratwig Hours Opsrotlnp Horfi o lubricant
Generator Bearing WB 384-g_______96 OE Air Cleaner
L —48 OE Crankcase Fill
Cold Weather Note. Below 0° F. drain L Capacity 2'/j Qt$.
crankcase. Refill cri ikcase with 2 qts. 4 1 B 1_
oe-sae io and mark this level "X" on the A~X ------4 Crankcase Level—
level gage. This new level b below the ['''NX; ' Check Level
Indicated full mark. Add !6 qt. of gasoline I ' TVs V* ■'''
and run engine five minuter During opera- I Ln*1' 1 I . 1\ ® / F ~ - Oil Base
tion and before shut-down add OE-SAE I ) I 1K I g. * * a Q, <*X*T* irv • t ., . . .
io »-x-^to.^oOTr.Pl... f | o p ’
l...l.ilb OE-SAE 10.nd odd ll Jjf . / ) OO HOT IUEEICATE
gasoline to fvll mark on gage. un engine *■—a / / / ------/ Unk passing through electric booster, commutator.
five minutes to mix offer stopping. r-~Vx~\~^S _ br- X. ------- * X< from bearing with Solvent, dry cleaning. Refill with
HU I L J about one tablespoonfvl of WB.
CRANKCASE — Drain only when engine is thoroughly OIL CAN POINTS —Every 48 operating hours place
warm. Refill to "High" mark on bayonet goge. one drop of OE on throttle shaft bearings of corbu-
C„, .1 »i. O. io.b.r.lo, M.
tonleMd »M o_ oM wpwwd. .11 l.-.l b.luw lb. "to.” murk on bo,on.I .eg.. AoU b.o-.ngu
conflicting lubrication instructions dated prior to 26 July 1944.
er ORDER Of THE SECRETARY OF WAR: ----- KEY------
G C MARSHALL, -----------------------------------------------------------------------------------------------------------
OFFICIAL Chief of Stall. LOWEST ANTICIPATED AIR TEMPERATURE
J A ULIO, ____________________ above + 32° F. +32° F. Io 0° F. below 0° F.
^eAdZn. General ' OE-CEANKCASE------------------SAE 30--------------------------------------
EXCEPT CRANKCASE SAE 30 SAE 10 PS No. 5001 I) WB—GREASE, flenerol purposo. No. 2—All temporoturos
PS—OIL, lubricating, preservative, special
This order to bo kept In the top panel cable compartment.
Figure 6. War Department Lubrication Order 5001.
14
TM 8-630
26-28
MAINTENANCE INSTRUCTIONS
Section XIII. LUBRICATION
26. LUBRICATION, a. War Department Lubrication Order 5001 (fig. 6)
illustrates the parts which require lubrication and specifies the lubricants and
the intervals of lubrication under all climatic conditions.
b. Records. WD Form 48, Drivers Trip Ticket and Preventive Maintenance
Service Record, will be used to keep proper lubrication intervals. WD,
AGO Form 468, Unsatisfactory Equipment Report, can be used to forward
notations of lubrication failures to proper authorities.
Section XIV. PREVENTIVE MAINTENANCE SERVICES
27. GENERAL, a. To insure mechanical efficiency it is necessary that the
equipment be systematically inspected at designated intervals in order that
defects may be discovered and corrected before they result in serious damage.
The scheduled preventive maintenance services prescribed in this section are
designed to insure maximum efficiency in the operation of the unit.
b. The general inspection or servicing of each item applies also to any
supporting member or connection, and generally includes a check to see
whether the item is in good condition, correctly assembled, secure, and not
excessively worn.
c. The inspection for good condition is usually an external visual inspection
to determine whether the unit is damaged beyond safe or serviceable
limits. The term good condition is explained further by the following descriptions:
not bent or twisted, not chafed or burned, not broken or cracked, not
bare or frayed, not dented or collapsed, not torn or cut.
d. The inspection of a unit to see that it is "correctly assembled” is
usually an external visual inspection to see whether it is in its normal assembled
position in the unit.
e. The inspection of a unit to determine if it is "secure” is usually an
external visual examination, a hand feel, or a pry-bar check for looseness. Such
an inspection should include any brackets, lock washers, lock nuts, locking
wires or cotter pins used in the assembly.
f. 'Excessively worn” is generally understood to mean worn close-to
or beyond serviceable limits, and likely to result in a failure if not replaced
before the next scheduled inspection.
28. OPERATORS SERVICE (first echelon), a. Operators preventive maintenance
services are listed on the back of the "Drivers Trip Ticket and Preventive
Maintenance Service Record,” WD Form 48 and are prepared to cover gasoline
engine powered equipment of all types and models. Items peculiar to
this equipment but not listed on WD Form 48 are covered under items with
which they are related. Those items that are listed on the form that do not
pertain to this equipment are omitted from the procedures as written in this
section.
b. The items listed on WD Form 48 that apply to this equipment are
expanded in this section to provide specific procedures or references to proper
paragraph for accomplishment of the inspections and services. These procedures
are arranged to facilitate their execution and to conserve the time
of the operator, and are not necessarily in the numerical order as given on
WD Form 48. The item numbers, however, are identical with those shown
on that form.
15
TM 8-630
28-30
X-RAY FIELD UNIT GENERATOR
c. Any defects or unsatisfactory operating characteristics beyond the scope
of first echelon to correct must be reported at the earliest opportunity to the
designated individual in authority.
29. BEFORE OPERATION SERVICES, a. This inspection schedule is designed
primarily as a check to see that the equipment has not been tampered
with or sabotaged, that engine oil and fuel have not leaked out, and that
nothing has happened to change conditions of operation since the last after
operation service was performed.
b. The before operation service consists of inspecting the items in the
following schedule according to the procedures prescribed, and correcting
or reporting any deficiencies. Upon completion of the service, results should
be reported promptly to the designated individual in authority.
(1) Item 1. Tampering or damage. Look for any damage to equipment
and for any signs of tampering or sabotage. To facilitate starting the engine,
dry the spark plugs and wiring if they appear wet. See that equipment is
placed in a level position and on a firm foundation.
(2) Item 3. Fuel and oil. See that fuel tank is full, adding fuel, gasoline
(unleaded and undyed) 62 octane number (U.S.A. 2-116 Amend 2),
if required. The oil level in crankcase should be at the "High” mark on the
oil filler gauge. (See fig. 5, (16).) Check level and add specified oil (par.
26) if required. Inspect for any foreign material in either fuel or oil that
might cause damage to the engine and correct if found before starting engine.
Any appreciable loss in either fuel or oil since the after operation. services
must be investigated and the cause corrected or reported.
(3) Item 6. Leaks, general. Look for fuel or oil leaks. Trace source
and correct or report.
(4) Item 4. Accessories. Inspect carburetor, air cleaner, fuel tank, muffler
and governor to see that they are secure and correctly assembled. Make
sure the soil around the grounding rod is moist. Inspect booster coil conduit
and spark plug cables making certain connections are tight and cables and
conduit are clean, and free from water or moisture.
(5) Item 7. Engine warm-up. (a) Open full tank shut-off petcock
(fig. 5, (9)) and close choke. The operation of the choke should be in accordance
with instructions in Item 8 which follows.
(h) Wind the starting rope around the starter rope pulley (fig. 5,
(6) ) and give a strong, steady pull the full length of the rope. Then proceed
according to instructions given in Item 8.
(6) Item 8. Choke. When starting a cold engine keep the manual
choke control (fig. 5, (13)) pulled out for first 3 or 4 turns. If engine
fails to start push choke control completely in and continue cranking for
several turns. Then repeat entire procedure until engine starts. This will
prevent overchoking. When engine starts adjust choke control so that engine
runs without surging or missing. Gradually push choke control inward as
engine warms up until it will operate smoothly with choke control pushed
completely in. Never operate with the choke control partly out.
(7) Item 25. During the operation check. As soon as the engine starts,
observation of the during operation service should begin.
30. DURING OPERATION SERVICES, a. While the equipment is operating
listen for any sounds such as rattles, knocks, squeals, or hums that would
16
TM 8-630
30-32
MAINTENANCE INSTRUCTIONS
indicate trouble. Look for smoke, and be on the alert to detect any unusual
odor that might indicate unsatisfactory operation, overheating, or fuel and
oil leaks. Use information on trouble shooting (sec. XV) to aid in locating
cause of unsatisfactory operation.
b. During operation, services consist of observing Item 31, below, according
to the procedures prescribed, and immediately investigating any indications
of serious trouble. Notice minor deficiencies to be corrected or
reported at the earliest opportunity, usually the next scheduled halt.
Item 31. Engine and controls. Be on the alert at all times while the
equipment is operating to detect any unusual operating characteristics such as
fluctuating, excessive, or low speed. Note any looseness or binding in governor
and booster linkage. Observe for any looseness that may develop in
any part of the equipment or its skid and mounting. Use information on
trouble shooting. (See par. 35.)
31. AT STOP SERVICES, a. Caution-. Be sure to disconnect the X-ray load
before stopping the engine. Stop the plant by pressing one of the stop buttons
(fig. 5, (19)) located on the blower housing of the engine. It should
be held in until the engine stops.
b. At stop services may be regarded as minimum maintenance and
should be performed under all conditions even though more extensive scheduled
maintenance services can not be accomplished at the prescribed interval.
c. At stop services are to be performed between periods of operation or
at least every 2 hours of operation. They consist of investigating any deficiencies
noted during operation, and inspecting the following items according
to the prescribed procedures. In either case, any deficiencies should be corrected
or reported.
(1) Item 38. Fuel and oil. Check for adequate supply of fuel, (par.
29b) to run until next scheduled stop and replenish if needed. Add engine
oil of correct grade (par. 26) if necessary to bring level to "High” mark on
oil filler gauge.
(2) Item 46. Leaks, general. Look for any fuel or oil leaks on equipment
mount and at all connections.
(3) Item 47. Accessories. Examine air cleaner, breather tube, carburetor,
ignition breaker box, fuel tank, fuel pump, and exhaust muffler for looseness.
Be sure ground around grounding rod is moist.
32. AFTER OPERATION SERVICES, a. Caution-. Be sure to disconnect the
X-ray load before stopping the engine. Stop the engine by pressing one of
the stop buttons located on the blower housing of the engine. It should be
held in until the engine stops.
b. After operation servicing is particularly important because at this
time the operator inspects and services the equipment to detect and correct
any deficiencies first echelon personnel is authorized to correct and to prepare
it so it is ready for use at any time that it is needed. The before operation
service, with a few exceptions, is then necessary only to be certain that the
equipment is in the same condition in which it was left upon completion of
the after operation service. The after operation service should never be
entirely omitted, but may be reduced under extreme conditions to the bare
fundamental services prescribed for the at stop service.
c. When performing the after operation service the operator must re17
TM 8-630
32
X-RAY FIELD UNIT GENERATOR
member and consider any irregularities noticed during the operation of the
equipment and found at the stop service.
d. The after operation services are to be performed after each day or
8 hours of operation. They consist of inspecting and servicing the following
items according to the prescribed procedures. Those items marked with
an asterisk (*) require additional services weekly or every 48 operating
hours, whichever occurs first, the procedures for which are given in (£) of
each applicable item.
(1) Item 54. Fuel and oil. Wipe gasoline tank filler cap clean and remove
and see that air vent hole is open. (See par. 44b.) Fill tank with fuel
(par. 29b) and replace cap. Check crankcase oil level and replenish with
correct grade of engine oil (par. 26) if needed to bring level to "High”
mark on oil filler gauge.
(2) Item 55. Engine operation. Investigate any deficiencies or unusual
operating characteristics noted during operation. (See par. 35.) Correct or
report. See that cooling fins on cylinders are clean.
(3) Item 63. * Accessories. (a) Examine breather tube, carburetor, ignition
breaker box, fuel tank, fuel pump, and exhaust muffler to see that they
are in good condition, clean and secure.
(£) (Weekly'). Tighten all loose mountings and line connections. Close
fuel tank shut-off petcock. Clean fuel pump bowl and screen. (See par. 45a.)
Check for leaks after engine starts.
(4) Item 64- ^Electrical wiring, (a) Examine booster conduit and
spark plug cables to see that they are in good condition, well supported, clean,
and properly connected.
(b) (Weekly). Clean booster conduit, spark plug cables and shielding,
and see that all connections are secure.
(5) Item 65. Air cleaner. Check air cleaner to see if it is excessively
dirty, and if so remove and clean. (See par. 48a.)
(6) Item 73. Leaks, general. Examine the entire equipment thoroughly
for indications of fuel or oil leaks.
(7) Item 67. Engine controls. Examine the engine and accessory controls
and linkage to see that they are in good condition, secure and operate
freely. Close fuel tank shut-off petcock.
(8) Item 82. ^Tighten, (a) No daily tightening is required other than
where inspection shows looseness of accessories or mountings.
(b) (Weekly). Check all engine mounting, base and skid bolts, exhaust
and intake manifold screws, breather tube and carburetor mounting screws,
and tighten as required.
(9) Item 83. ^Lubricate as needed, (a) Lubricate controls according
to instructions. (See par. 26.)
(b) (Weekly). Lubricate all points shown on WD Lubrication Order
5001 (par. 26) requiring weekly lubrication.
(10) Item 85. *Tools and equipment, (a) Check to see that all tools,
extra equipment, and spare parts are present. (See figs. 2 and 3.)
(b) (Weekly). Check to see that all tools, extra equipment, and spare
parts are present and in working and usable condition. (See figs. 2 and 3.)
18
TM 8-630
33
MAINTENANCE INSTRUCTIONS
33. SECOND ECHELON PREVENTIVE MAINTENANCE, a. The numbers
of the preventive maintenance procedures given in the chart which follows,
are identical with those outlined in WD, AGO Form 461. Certain items on
the work sheet that do not apply to this equipment are not included in the
procedures in this manual. In general, the numerical sequence of the
items on the work sheet is followed in the chart, but in some instances there
is deviation for conservation of time and effort.
b. Special services are directed by repeating the item numbers in the
columns which indicate the interval at which the services are to be performed,
and show the parts or assemblies which are to receive certain mandatory services.
For example, an item number in one or both columns opposite a procedure
marked "tighten” means that the actual tightening of the object must
be performed. The special services are described as follows:
(1) Adjust. Make all necessary adjustments in accordance with the instructions’
available in paragraphs pertinent to the part or assembly.
(2) Clean. Clean components and parts of the equipment indicated with
dry cleaning solvent, unless otherwise directed to remove excess lubricant,
dirt, and other foreign material. If parts have been removed from equipment,
they should be rinsed in clean solvent and dried thoroughly before
installing. Be sure to keep parts clean until reassembled and installed. Clean
the protective grease coating from new parts since this material is not a
good lubricant.
(3) Special lubrication. This applies either to lubrication operations
that do not appear on the WD Lubrication Order or to items that do appear
on the order but should be performed in connection with the maintenance
operations if components have to be disassembled for inspection or service.
(4) Service. This usually consists of performing certain operations such
as draining and refilling oil base with oil.
(5) Tighten. All tightening operations must be performed with sufficient
force on the wrench handle (torque) to tighten the unit sufficiently
to hold under jarring and vibration but still not damage threads or cause
distortion. Tightening will always be understood to include the correct installation
of lock washers, lock nuts and cotter pins provided and necessary
to secure the tightening.
c. The procedures for performing operations for each item in the 96
operating hours of monthly (whichever occurs first) and 384 operating hours
or 6 months (whichever occurs first) schedule are described in the chart
below. Each page of the chart has two columns at its left edge corresponding
to the monthly or 6 months maintenance intervals, respectively. It will be
found that a particular procedure may not be required at both intervals. In
order to determine those procedures that are to be performed, follow the
column corresponding to the maintenance interval that is due, and wherever
an item number appears in that column perform the operations indicated
opposite that number.
d. The frequencies of preventive maintenance services outlined herein
are considered a minimum requirement for normal operation of the equipment.
Under unusual operation conditions it may be necessary to perform the maintenance
services more frequently.
19
TM 8-630
33
X-RAY FIELD UNIT GENERATOR
RUNNING TEST
384
operating
hours or
6 months
96.
operating
hours or
1 month
BEFORE OPERATION SERVICE. Perform before
operation service as outlined in paragraph 29 to determine
whether equipment is supplied with fuel and
oil, and to make it ready for running test.
ENGINE. Operate engine with and without load and
listen for knocks, rattles, hums and any other unusual
noises that would indicate trouble. Notice any tendency
to surge, stall, or miss. (Under load, readings
on the X-ray machine at 85 K.V.P. should have a
range from 5 Ma. to 25 Ma.) Look for excessive
smoking from the exhaust that would indicate too rich
carburetor adjustment or high oil consumption. Be on
the alert for any odors that might mean undesirable
operation. (Engine speed should be 1,800 RPM.) Use
information on trouble shooting. (See sec. XV.)
UNUSUAL NOISES. Be on the alert for any unusual
noises that would indicate trouble in the generator;
loose, damaged or unsatisfactory operating accessories,
or mounting bolts that need tightening. Use information
on trouble shooting. (See par. 36.)
LEAKS. Examine the equipment and mounting in
general, and all lines and connections, to detect any
signs of fuel or oil leaks. Look particularly for signs
of oil being thrown from the ventilating openings between
the engine crankcase and generator frame which
normally indicates leakage from the rear main bearing.
Leakage at this point should be reported to the designated
individual in authority.
20
1 1
9 9
10 10
14 14
TM 8-630
33
MAINTENANCE INSTRUCTIONS
MAINTENANCE OPERATIONS
384
operating
hours or
6 months
96
operating
hours or
1 month
18
18
19
20
20
31
33
33
84
34
34
35
35
36
18
18
19
20
20
31
33
84
34
34
35
36
CYLINDER, HEAD, AND GASKET. Clean. Follow
instructions for removing carbon. (See par. 52.)
TIGHTEN. Tighten cylinder head nuts evenly and
securely. (See par. 52d.)
VALVE MECHANISM. Adjust. Adjust valve tappet
clearances to .006 inch — .008 inch for intake and
.008 inch to .010 inch for exhausts with engine cold.
(See par. 52.)
SPARK PLUGS. Clean. Clean and inspect plugs and
replace if necessary. (See par. 42.)
ADJUST. Set electrode gaps to .025 inch to .030 inch.
(See par. 42d.)
BREAKER POINTS. Adjust. Reface the points and
adjust the gap as specified on the plate near the ignition
breaker box. If the contacts are badly burned,
pitted, or damaged replace them. (See par. 38.)
MANIFOLDS. Observe the intake and exhaust manifolds
and breather tube to see that they are in good
condition, secure, and that manifold gaskets appear to
be in good condition and not leaking.
TIGHTEN. Tighten all manifold and breather tube
nuts.
MUFFLER. Examine exhaust manifold to see that it
is in good condition and not clogged.
AIR CLEANER. Clean and service. Follow instructions
for cleaning and servicing air cleaner. (See
par. 48.)
TIGHTEN. Tighten connecting screws evenly and
securely.
BREATHER TUBE AND SCREENS. See that they
are in good condition, correctly installed and secure.
CLEAN. Remove breather tube assembly and wash
tube and screen in dry cleaning solvent and dry. (See
par. 49.)
CARBURETOR. (Choke, linkage, governor.) See
that these items are in good condition, correctly assembled
and securely installed. Examine particularly
the governor arm ball joint to assure that it operates
freely and is lubricated properly (par. 26), and that
none of the other connections of the governor to carburetor
linkage are binding.
21
TM 8-630
33
X-RAY FIELD UNIT GENERATOR
384
operating
hours or
6 months
96
operating
hours or
1 month
37 37 FUEL FILTER, SCREEN AND LINES. See that fuel
tank shut-off petcock is closed. Inspect fuel lines from
fuel pump to fuel tank and carburetor to see that they
are in good condition and that connections are tight
and not leaking.
37 37 CLEAN. Remove and clean fuel sediment bowl and
screen. Clean fuel lines. (See pars. 44d and 45b.)
Check for leaks after engine starts.
38 38 FUEL PUMP. Inspect fuel pump for leaks, good condition
and to see that it is securely mounted.
38 38 CLEAN. Clean bowl and screen. (See par. 45a.) .
82 82 FUEL TANK AND FITTINGS. Inspect fuel tank
to see that it is in good condition and securely mounted.
Examine fuel tank cap for defective gasket and plugged
vent. Check fuel shut-off valve and connections for
good condition and security. Be certain tank and fittings
do not leak.
27 27 GENERATOR. Remove bell housing band and examine
commutator and collector rings for good condition.
Inspect brushes for good condition. (See par.
55.)
27 27 CLEAN. If interior surfaces are oily or greasy wipe
them clean with a dry cloth.
27 TIGHTEN. Tighten armature through stud nut.
80 80 FRAME. Inspect frame skid and mount to see that
they are in good condition and that unit is securely
bolted to them.
85 85 LUBRICATION. Lubricate as directed in WD Lubrication
Order 5001. (See par. 26.)
131 131 TOOLS. Check tools to see that they are all present.
(See fig. 2.) Inspect to see that tools are in good
condition, clean and properly stowed.
135 135 PUBLICATIONS. Check to see that WD Lubrication
Order 5001 is present and legible.
138 138 SPARE PARTS. Check to see that the prescribed
number of spare parts are present (fig. 3), in good
condition, and properly stowed.
142 142 FINAL RUNNING TEST. Repeat items 1 through
14 of "running test.”
22
TM 8-630
34-35
MAINTENANCE INSTRUCTIONS
Section XV. TROUBLE SHOOTING
34. GENERAL, a. The possible troubles and remedies listed below will assist
in determining the cause of unsatisfactory operation. A separate list is
provided for the engine and the generator. If the remedy is not given, reference
is made to a paragraph where more complete information will be found.
Only those causes which can be detected during operation or during first and
second echelon maintenance service are listed. Therefore, if the trouble still
exists after performing the listed remedies the unit requires higher echelon
service.
b. The information in this section applies to operation of the unit under
normal conditions. If extreme conditions are encountered, it is assumed the
unit has received the attention outlined for operation under unusual conditions.
(See sec. IX.)
35. ENGINE, a. Engine fails to start or is
Possible cause
Improper electrical load.
Oil too heavy due to temperature
drop.
Fuel tank empty.
Air cleaner clogged.
No spark or weak spark.
Contaminated engine fuel.
b. Engine starts but does not
Possible cause
Overheating.
Air lock in fuel supply system.
Screen in fuel pump clogged.
Fuel lines clogged.
Carburetor dirty.
Contaminated engine fuel.
Short circuit in conductor cable.
Short circuit in X-ray machine.
hard to start.
Possible remedy
Use unit only with specified X-ray
machines. (See par. 3a.)
Change oil. Follow lubrication instructions.
(See par. 26.)
Refill.
Clean. (See par. 48.)
See possible causes and remedies for
this condition. (See par. 35g.)
Drain and refill.
continue running.
Possible remedy
See possible causes and remedies for
this condition. (See par. 35c.)
Open fuel tank shut-off petcock.
Clean gas tank filler cap vent. (See
par. 44b.)
Remove and clean. (See par. 45a.)
Remove and clean. (See parss 44d
and 45b.)
Report to proper authority. Do not
disassemble.
Drain and refill.
Replace with new cable.
Report to proper authority.
23
TM 8-630
35
X-RAY FIELD UNIT GENERATOR
c. Engine overheating.
Possible cause
Exhaust back-up due to improper
size exhaust vent.
Exhaust muffler clogged.
Improper ventilation.
Excessive carbon in cylinder heads
and on piston.
Cooling fins dirty.
Engine oil level low.
Incorrect valve tappet adjustment.
Possible remedy
Correct vent pipe size. (See par. 9d.)
Replace.
Remove all carrying case panels.
Move unit into shaded outside
area if possible.
Remove carbon. (See par. 52.)
Clean.
Fill to full mark on gauge.
Adjust. (See par. 52c.)
d. Excessive engine oil consumption.
Possible cause Possible remedy
Overheating. See possible causes and remedies of
the condition. (See par. 35c.)
Engine oil held above full mark.
Oil leaks at gaskets and seals.
Leak in oil base.
e. Engine lacks power.
Possible cause
Poor compression.
Weak spark.
Air cleaner clogged.
Contaminated engine fuel.
Overheating.
Incorrect valve tappet adjustment.
Allow at least 5 minutes to elapse,
after engine stops for oil to drain
back into base, before checking.
Add oil only to full mark on
gauge.
Report to proper authority.
Report to proper authority.
Possible remedy
See possible causes and remedies for
this condition. (See par. 35f.)
See possible causes and remedies for
this condition. (See par. 35g.)
Clean. (See par. 48.)
Drain and refill.
See possible causes and remedies for
this condition. (See par. 35c.)
Adjust. (See par. 52c.)
24
MAINTENANCE
f. Poor compression.
Possible cause
Incorrect valve tappet adjustment.
Loose spark plug.
Loose cylinder head.
Head gasket leaking.
Piston cracked or broken.
Valves sticking.
g. No spark or weak spark.
Possible cause
Dirty or loose wire connections.
Incorrect spark plug gap.
Carbon deposits on spark plug porcelains.
Cracked spark plug porcelain.
Pitted breaker points.
Incorrect breaker point clearance.
Broken ignition breaker spring.
Defective condenser.
Stop wire grounded.
TM 8-630
35
INSTRUCTIONS
Possible remedy
Adjust. (See par. 52c.)
Tighten.
Tighten. (See par. 52d.)
Replace. (See par. 52.)
Report to proper authority.
Report to proper authority.
Possible remedy
Clean and tighten.
Set gap. (See par.’ 42d.)
Clean or replace with new plug.
(See par. 42b.)
Replace with new plug.
Reface. (See par. 38.)
Reset. (See par. 38.)
Replace with new spring. (See par.
38.)
Replace with new condenser. (See
par. 38.)
Tape worn insulation.
h. Popping, spitting, and pinging (spark knock).
Possible cause Possible remedy
Valve tappet clearance too close. Adjust. (See par. 52c.)
Excessive carbon deposits causing Clean carbon. (See par. 52.)
cylinder head hot spots.
Overheating. See possible causes and remedies for
this condition. (See par. 35c.)
25
TM 8-630
36-37
X-RAY FIELD UNIT GENERATOR
36. GENERATOR, a. Generator heating.
Possible cause
Improper electrical load on unit.
Short circuit in conductor cable.
Short circuit in X-ray machine.
Excessive engine speed.
b. Generator does not produce.
Possible cause
Brush rig not set in neutral position.
Brushes binding in holders.
Brushes worn to less than % inch.
Brush springs broken.
Brush spring resting in holder.
Dirty commutator.
Commutator bar loose or projecting
above others.
Mica extending above commutator
bar surface.
Engine speed too slow.
Break in conductor cable wire.
c. Noise in brushes.
Possible cause
High and low commutator bars.
Mica extending above commutator
bars.
Possible remedy
Use unit only with specified X-ray
machine. (See. par. 3a.)
Replace with new cable.
Report to proper authority.
Report to proper authority.
Possible remedy
Correct setting. (See par. 55j.)
Loosen in holders. (See par, 55b.)
Replace with new brushes. (See par.
55g.)
Replace with new spring. (See par.
55h.)
Position correctly. (See par. 55h.)
Report to higher authority.
Report to proper authority.
Report to proper authority.
Report to proper authority.
Replace with new cable.
Possible remedy
Report to proper authority.
Report to proper authority.
Section XVI. IGNITION SYSTEM SERVICE
37. GENERAL, a. This section contains instructions on the engine ignition
system for the personnel of the first and second echelons to enable them to
perform the scheduled preventive maintenance services (sec. XIV) and to
26
TM 8-630
37-38
MAINTENANCE INSTRUCTIONS
replace the spare parts available to the first and second echelons. No other
services will be attempted.
b. Ignition current is furnished by a flywheel type magneto. The magneto
proper is located inside the blower wheel and consists of the rotor or magnets,
integral with blow wheel, and the stator assembly mounted on the gear cover.
The stator assembly includes the right-hand coil (fig. 7, (3)), left hand coil
(fig. 7, (4)), laminated coil shoes (fig. 7, (2)), and the back plate (fig. 7,
(5)). The ignition breaker is mounted atop the crankcase. The breaker arm
(fig. 7, (39)) and arm point (fig. 7, (36)) are operated by a plunger (fig.
7, (40)) which rides on the camshaft. A condenser (fig. 7, (43)), connected
across the points, greatly increases the spark intensity and the life
of the breaker points. High tension current is generated within the coils, each
of which is connected to a spark plug by a high tension cable.
38. IGNITION BREAKER ASSEMBLY, a. Breaker arm and points (fig. 3,
(1)) consist of the following five component parts:
(1) Stationary point. The stationary point (fig. 7, (37)) fastens to
the ignition breaker.box (fig. 7, (35)).
(2) Stationary point lock nut. K brass hex nut (fig. 7, (38)) locks the
stationary point in position.
(3) Arm point. The arm point (fig. 7, (36)) is an integral part of the
breaker arm.
(4) Arm to ground wire. Grounds arm to box.
(5) Breaker arm. The breaker arm (fig. 7, (39)) pivots on the arm
stud (fig. 7, (42)). It is lifted by the plunger and depressed by the spring.
b. Disassembling. (1) Remove ignition breaker box cover.
(2) Compress and remove spring.
Caution-. Cover rear generator vent openings to prevent dropping the
ignition breaker spring into the generator.
(3) Remove the breaker arm from arm stud.
c. Cleaning disassembled parts. Use a clean lintless cloth, dampened
with dry cleaning solvent to wipe all parts of the ignition breaker and the
interior of the ignition breaker box. Thoroughly wipe all parts with a dry
clean lintless cloth.
d. Inspecting points. Determine if points are burned, pitted, or have a
carbonlike deposit. Reface the points if any of these conditions exist.
e. Refacing points. Use the ignition point file (fig. 2, (5)), to reface
the points. File points until each face is free of pits or deposit and has a
clean metallic appearance.
f. Replacing points. (1) If points cannot be refaced, replace with a new
breaker arm and points. (See fig. 3, (1).)
(2) Replace disassembled arm with new arm.
(3) Loosen lock nut on stationary point.
(4) Remove stationary point.
(5) Install new stationary point in breaker box.
(6) Fasten lock nut.
g. Reassembling. (1) Place breaker arm on arm stud.
(2) Compress spring and slip into position.
(3) Connect arm to ground wire on terminal at inside rear of ignition
breaker box.
27
TM 8-630
38
X-RAY FIELD UNIT GENERATOR
®L ®)®L ®®®®®®®®®
nSW)
®V Mr/ \ /
CD'
®\^ ===: \
^4^1 / /o W®^\ \ • u~~ ^x. ।
™pjSM(^yt'x A \\ vI j sSB\ /®/sz'-x
\Ks^s/®
(T) //^T^Ax \ /
Zw^^aa rfL/
//./ ZP7^®
@@@@@~@@(3y(35X3^”'^(33)
Figure 7. Ignition, governor-booster, and air cleaner assemblies.
28
TM 8-630
38
MAINTENANCE INSTRUCTIONS
Med.
Dept. No. Nomenclature
Med.
Dept. No. Nomenclature
1. 9R0077I Wire, magneto to con23.
TR02080 Wrench, ignition point, for
denser. nut screw size 5.
2. 9R0076I Shoe, magneto coil, lami24.
.025 inch feeler gage on
nated. ignition point wrench,
3. 9R00762 Coil, magneto, right. SR0I824.
4. 9R00764 Coil, magneto, left. 25. Electrodes of spark plug,
5. 9R00760 Plate, back, magneto. 9R00780.
6. 9R00662 Weight, governor. 26. 9R00734 Cleaner, air.
7. 9R00667 Cup and stud, governor. 27. 9R00733 Adapter, air cleaner.
8. 9R00866 Shaft and paddle, gover28.
9R00737 Screw, locking, air cleaner
nor. • adapter.
9. 9R00805 Spring, governor-booster. 29. 9R00736 Screen, breather tube.
10. 9R00852 Stud, spring, governor. 30. 9R00709 Gage and chain, oil filler.
II. 9R00668 Rod, arm, governor. 31. 9R00707 Cap and bushing, oil filler.
12. 9R00670 Joint, ball, governor. 32. Oil level full mark.
13. 9R00858 Cover, housing, booster. 33. Oil level low mark.
14. 9R00856 Housing, booster. 34. 9R009I4 Wire, condenser to points.
15. 9R00864 Rod, control, throttle. 35. 9R00779 Box, ignition breaker.
16. 9R00844 Bracket, adjusting spring, 36. Arm point of breaker arm
governor. and points, 9R00772.
17. 9R00842 Nut, adjusting, governor 37. Stationary point of breaker
spring. arm and points, 9R00772.
18. 9R00660 Gear, camshaft. 38. SR00665 Nut, 5 x 40, hex, brass: For
19. 9R00654 Camshaft. locking stationary point.
20. Terminal of spark plug, 39. Breaker arm of breaker
9R00780. arm and points, 9R00772.
21. Porcelain of spark plug, 40. 9R00774 Plunger, breaker.
9R00780. 41. 9R00776 Spring, breaker.
22. Hex body of spark plug, 42. 9R00782 Stud, arm, ignition breaker.
9R00780. 43. 9R00766 Condenser, magneto.
Figure 7. Ignition, governor-booster, and air cleaner assemblies-—Continued.
29
TM 8-630
38-42
X-RAY FIELD UNIT GENERATOR
h. Resetting point gap. (1) Slowly turn starter rope pulley (fig. 5,
(6)) until the breaker plunger reaches its highest position. This in turn
opens the space between the stationary point and the arm point to the maximum
gap.
(2) Loosen the lock nut on the stationary point.
(3) Turn the stationary point to open or close the gap.
(4) Check the breaker point gap specified on the plate fastened to
generator near the ignition breaker box. If plate is missing set gap at .020
inch.
(5) Select the required leaf from the feeler gauge. (See fig. 2, (22).)
(6) Place the correct feeler gauge leaf between the stationary point and
the arm point. Turn stationary point until feeler gauge leaf touches both
points. Do not turn stationary point up so far as to raise the arm off the
plunger.
(7) Tighten stationary point lock nut.
i. Fasten ignition breaker box cover in place.
39. SPARK PLUG CABLES. To clean and inspect—
a. Remove spark plug shields.
b. Remove spark plug cables from the spark plugs.
c. Inspect spark plug ends of the cables.
d. Use ignition point file to clean any corfosion or deposit from cable
terminals.
e. Carefully inspect cable insulation for wear, frayed ends, or breaks.
40. MAGNETO AND IGNITION BREAKER TEST. a. Before proceeding
with this test, check for any leaks or pools of gasoline on or about the unit
to eliminate any fire hazard.
b. Support plug ends of cables in such a manner that there is a 1/g-inch
air gap between each cable end and a cylinder fin.
c. Grasp the starter rope pulley with both hands and quickly turn it
counterclockwise.
d. Spark will jump the %-inch air gap if the magneto and ignition
breaker are functioning properly.
e. Connect cable to spark plug, put spark plug shields in place and
fasten.
41. MAGNETO CONDENSER, a. If spark fails to bridge the 1/^-inch air
gap when tested (par. 40), it may be due to a break-down of the magneto
condenser. (See fig. 3, (4).)
b. Replacing magneto condenser.
Note. It is impossible to repair a condenser; it must be replaced.
(1) Disconnect wires from condenser.
(2) Remove condenser from ignition breaker box.
(3) Install new magneto condenser.
(4) Connect wires to condenser.
(5) Fasten ignition breaker box cover in place.
(6) Repeat magneto and ignition breaker test. (See par. 40.)
42. SPARK PLUGS, a. Removing. (1) Remove spark plug shields.
(2) Disconnect cables from spark plugs.
30
TM 8-630
42-43
MAINTENANCE INSTRUCTIONS
(3) Use the spark plug wrench (fig. 2, (23)) to remove the spark
plugs from the cylinder heads. Do not misplace the spark plug gaskets.
b. Cleaning spark plugs. (1) Use a clean cloth, dampened with dry
cleaning solvent to wipe any oil and dirt from the plug. Be certain to
thoroughly clean the terminal (fig. 7, (20)) and the porcelain (fig. 7, (21)).
(2) Follow with a clean dry cloth.
(3) Use a knife blade or small screw driver to remove deposits from
the portion of porcelain within the metal hex body. (See fig. 7, (22).) Extreme
care must be exercised in this operation. Do not exert undue force because
the porcelain is easily cracked and the spark plug rendered useless.
(4) Wipe the plug with a clean dry cloth.
c. Inspecting spark plugs. (1) Very carefully inspect the porcelains for
cracks or chips.
(2) Inspect electrodes to determine if there is sufficient metal remaining
to permit proper resetting of the gap.
d. Resetting spark plug electrode gap. (1) Proper electrode gap is
.025 inch.
(2) Use a screw driver to bend the outer electrode; do not bend the
center electrode until .025 inch gap is obtained. 1
(3) Wipe the spark plug with a clean dry cloth.
e. Testing spark plugs. (1) Predetermine proper functioning of magneto
and ignition breaker. (See par. 40.)
(2) Connect cables to spark plugs.
(3) Place spark plugs on cylinder cooling fins in such a manner that
only the metal hex body of the spark plug touches the cooling fins.
(4) Spin the starter rope pulley.
(5) Both spark plugs should arc only between the electrodes and both
should arc at the same instant.
f. Replacing spark plugs. (1) If the spark plug test (par. 42e) indicates
either of the plugs to be faulty replace both with new spark plugs.
(See fig. 3, (14).)
(2) Wipe plugs with a clean cloth.
(3) Place gasket on spark plugs.
(4) Screw spark plugs into cylinder heads and tighten with the spark
plug wrench.
(5) Connect spark plug cables.
(6) Fasten spark plug shields in place.
Section XVII. FUEL SUPPLY SYSTEM SERVICE
43. GENERAL, a. This section contains instructions on the fuel supply system
for personnel of the first and second echelons to enable them to perform
the scheduled preventive maintenance services (sec. XIV) and to replace the
spare parts available to the first and second echelons. No other services will
be attempted.
b. Fuel is stored in a 2-gallon tank mounted over the generator. The
fuel tank filler cap (fig. 5, (10)) is provided with a shut-off screw which
closes the air vent. The fuel tank shut-off petcock (fig. 5, (9)) is a means of
shutting off the flow of fuel from the tank to the fuel pump. Fuel tank line
(fig. 5, (14)) connects the fuel tank and the fuel pump. The fuel pump
draws the fuel from the tank through the fuel tank line and forces it through
31
TM 8-630
43-44
X-RAY FIELD UNIT GENERATOR
the carburetor fuel line to the carburetor. The air cleaner and carburetor are
essentially part of the fuel supply system but are covered separately. (See
sec. XVIII.)
c. Preparation for servicing fuel supply system. (1) Allow engine to
completely cool before servicing fuel supply system.
(2) Close fuel tank shut-off petcock.
(3) Place a clean 2-gallon container near fuel tank line.
(4) Disconnect swivel end of fuel tank line. Allow gasoline to drain
from the line into the container.
(5) Open filler cap shut-off screw.
(6) Open the shut-off petcock and drain the gasoline from the tank
into the container using any means necessary and available to limit spillage to
a minimum. x-
(7) Remove spark plug shields.
(8) Disconnect spark plug cables from spark plugs. Place cable ends in
such a position that they will not arc to any part of the unit.
(9) Place container near the carburetor fuel line.
(10) Disconnect swivel end of carburetor fuel line and drain gasoline
into container.
(11) Crank engine until gasoline is pumped from the interior of the
fuel pump. The fuel pump bowl (fig. 5, (15)) cannot be emptied in this
manner.
(12) Wrap any large rag around the flange of the fuel pump to absorb
the gasoline remaining in the fuel pump bowl when removing the bowl. Be
certain the engine is cool before proceeding.
(13) Loosen the bowl yoke nut. (See fig. 8, (7).)
(14) Swing the bowl yoke (fig. 8, (8)) clear of the bowl (fig. 8,
part (9)).
(15) Remove the bowl from the fuel pump.
(16) Remove both fuel lines.
44. FUEL TANK AND FITTINGS, a. Caution. Never attempt to repair a
fuel tank whether full or empty.
b. Cleaning filler cap vent. (1) Remove the filler cap from the tank
to avoid the possibility of dropping any part of the cap mechanism into the
tank.
(^) Unscrew filler cap.
(£) Compress the wire stop at the end of the cap chain and remove
from tank.
(2) Remove the chain loop from the shut-off screw.
(3) Remove shut-off screw from cap.
(4) Use a strand of wire or a needle to open the air vent through the
filler cap.
(5) Remove gasket from shut-off screw and replace with a new gasket.
(See fig. 3, (10).)
(6) Screw shut-off screw into filler cap.
(7) Put shut-off screw spring in place and clamp chain lock to screw.
(8) Remove gasket from tank and replace with new filler cap gasket.
(See fig. 3, (7).)
32
TM 8-630
44
MAINTENANCE INSTRUCTIONS
H gib* ]
\-LX^ V i|7,/ f t !* /z^ I—~— -■'“»■* ftpS) \& E 5 T ]n p——®
Med. Med. Med.
Dept. No. Nomenclature Dept. No. Nomenclature Dept. No. Nomenclature
I. 9R00750 Gasket, fuel pump adapter 5. 9R007I5 Elbow, carburetor. and breather tube. 6. 9R00752 Screen, fuel pump. II. 9R00743 Body, upper, fuel pump.
2. 9R00749 Rod, push, fuel pump. 7. 9R00753 Nut, bowl yoke, fuel pump. 12. 9R00744 Line, fuel, carburetor.
3. 9R0075I Adapter, fuel pump. 8. 9R00757 Yoke, bowl, fuel pump. 13. 9R00952 Body, lower, fuel pump.
4. 9R00748 Gasket, fuel pump. 9. 9R00754 Bowl, fuel pump. 14. 9R007I5 Elbow, carburetor.
Figure 8. Fuel pump assembly.
33
TM 8-630
44-46
X-RAY FIELD UNIT GENERATOR
c. Cleaning fuel tank shut-off petcock. Use a copper wire to remove
any sediment from petcock.
d. Cleaning or replacing fuel tank line. (1) Use a copper wire of sufficient
length, to remove any sediment from the line.
(2) If line is too tightly clogged to be opened with a wire or previous
inspection has disclosed a leak, replace it with a new fuel tank line. (See fig.
3, (13).)
e. Flush the shut-off petcock and fuel tank line. (1) Close the shut-off
petcock.
(2) Place a container below the shut-off petcock.
(3) Pour approximately l/2 gallon of gasoline into the tank.
(4) Open the petcock and allow gasoline to drain into the container.
This will remove any loose sediment from the shut-off petcock.
(5) Place a clean piece of cloth over the fuel tank cap opening to strain
the gasoline and using the same gasoline, repeat the process several times.
This will also flush any sediment from the tank.
(6) Install fuel tank line. Connect the stationary coupling first and then
the swivel end.
(7) Connect the fuel tank line to the fuel pump at the coupling marked
"In.”
45. FUEL PUMP. a. Cleaning or replacing bowl and screen. (1) Use a
clean cloth soaked with dry cleaning solvent to wipe the interior of the bowl.
In case of breakage, replace with a new fuel pump bowl. (See fig. 4, (1).)
(2) Lift the screen from the pump.
(3) Pour solvent through screen in both directions. Use care not to
puncture the screen.
(4) If screen is damaged, replace it with a new fuel pump screen. (See
fig. 4, (9).)
(5) Put a new fuel pump bowl gasket (fig. 3, (8)) in place.
(6) Reassemble screen and bowl by reversing procedure for disassembly.
b. Cleaning or replacing carburetor fuel line. (1) Use a copper wire,
of sufficient length, to remove any sediment from the interior of the line.
(2) Flush the line with solvent to remove loosened sediment.
(3) If line is too tightly clogged or leaks have been detected in previous
inspection, replace with a new carburetor fuel line. (See fig. 3, (12).)
(4) Connect carburetor fuel line to the fuel pump and the carburetor.
46. FUEL SUPPLY SYSTEM TEST. a. Prepare engine as for starting (par.
14a) but do not run engine.
b. Disconnect the carburetor fuel line at the carburetor.
c. Place the disconnected end of the carburetor fuel line in a clean empty
container.
d. Use the starter rope to crank the engine. After many turns the fuel
pump bowl should fill followed by the ejections of gasoline from the disconnected
carburetor fuel line.
e. Visually inspect for any leaks in the system.
f. Connect the carburetor fuel line to carburetor.
g. Connect the spark plug cables to the spark plugs.
h. Replace the spark plug shields.
34
TM 8-630
47-49
MAINTENANCE INSTRUCTIONS
Section XVIII. AIR CLEANER ASSEMBLY AND CARBURETOR SERVICE
47. GENERAL, a. This section contains instructions on the air cleaner assembly
and carburetor for the personnel of the first and second echelon of
maintenance to enable them to perform the scheduled preventive maintenance
services (sec. XIV) and to replace the spare parts available to the first and
second echelons. No other service will be attempted.
b. The air cleaner and breather assembly filters the air before entering
the carburetor and removes heated gases from the crankcase. The outside air
is drawn through the air cleaner (fig. 7, (26)) by the vacuum created during
each intake stroke of the engine. The air passes through the air cleaner adapter
(fig. 7, (27)) to the carburetor. Pressure within the crankcase is relieved
through the breather tube screens (fig. 7, (29)) into the adapter and the carburetor.
The carburetor mixes the air and the fuel before they enter the intake
manifold. The carburetor also houses the choke valve plate and the
throttle valve plate.
48. AIR CLEANER. To clean or replace air cleaner—
a. Remove the three screws which fasten the air cleaner to the adapter.
b. Soak and rinse the air cleaner in dry-cleaning solvent.
c. This should be done until the solvent flows from the air cleaner with
very little discoloration.
d. If the air cleaner is so dirty as to retard or prohibit the flow of solvent
through it or the operating conditions are known to have been severely dusty,
it should be replaced with a new air cleaner. (See fig. 4, (3).)
e. After cleaning with solvent soak the air cleaner for 1 hour in engine
oil of the type used in this unit. Allow air cleaner to drain before installing.
f. Put a new air cleaner gasket (fig. 4, (5)) in place.
g. Install the clean or new air cleaner on the adapter.
49. BREATHER TUBE SCREEN. To clean or replace breather tube screen—
a. Loosen the adapter locking screw. (See fig. 7, (28).)
b. Lift the adapter from the carburetor and the breather tube screen.
(See fig. 7, (29)-) It is not necessary to remove the air cleaner from the
adapter.
c. Mark position of booster bracket on breather tube.
d. Loosen both screws which fasten booster bracket to breather tube.
e. Remove booster bracket from breather tube.
f. Remove the two screws which fasten the breather tube screen to the
engine. ,
g. Use dry cleaning solvent to clean the screens by pouring through the
tube. Soak and rinse until solvent will pour from tube with very little discoloration.
h. If tube unit is damaged, replace with a new breather tube screen. (See
fig- 4, (7).)
i. Place a new breather tube gasket (fig. 4, (8)) in position.
j. Fasten breather tube to engine.
k. Place booster bracket on breather tube in previously marked position.
I. Insert and tighten both screws which fasten booster bracket to breather
tube.
m. Put adapter on breather tube and fasten to the carburetor.
35
TM 8-630
50-52
X-RAY FIELD UNIT GENERATOR
50. CARBURETOR. No carburetor service will be performed or attempted
by the personnel of the first and second echelons of maintenance.
Section XIX. CYLINDER HEADS AND VALVE MECHANISM SERVICE
51. GENERAL, a. This section contains instructions on the cylinder heads
and valve mechanism for the personnel of the first and second echelons of
maintenance to enable them to perform the scheduled preventive maintenance
services (sec. XIV) and to replace the spare parts available to the first and
second echelons. No other services will be attempted.
b. The cylinder heads support the spark plugs and form the combustion
chambers (fig. 9, (5)) over the cylinders and pistons. The electrodes of the
spark plugs extend into the combustion chambers. The exterior fins are a
means of dissipating the heat from the cylinder heads. The intake valve
(fig. 9, (23)) opens to permit the passage of the fuel-air mixture into the
combustion chamber during the intake' stroke of the engine and seals off the
combustion chamber during the compression, power, and exhaust strokes. The
exhaust valve (fig. 9, (24)) opens during the exhaust stroke to permit the
escape of the burned gases to the exhaust manifold and seals the combustion
chamber during the intake, compression, and power strokes. The valves are
opened when the camshaft lifts the valve lifters (fig. 9, (13) and (36)), and
are closed by the valve springs. (See fig. 9, (20) and (41).) Valve tappets
(fig. 9, (15) and (38)) are a means of adjusting the clearance between the
valve lifters and the valves.
52. REMOVING CARBON AND ADJUSTING VALVE TAPPETS, a. Disassembling.
(1) Remove spark plug shields.
(2) Remove spark plug cables.
(3) Remove spark plugs from cylinder heads.
(4) Remove screws which fasten the cylinder air housings to the cylinder
heads.
(5) Remove both cylinder air housings.
(6) Remove the six cylinder head nuts from each head.
(7) Remove cylinder heads.
(8) Remove cylinder head gaskets. (See fig. 9, (6) and (28).)
(9) Remove the four screws which fasten the intake manifold adapters
to the intake ports. (See fig. 9, (2) and (9).)
(10) Remove intake manifold adapters by pulling them free of the intake
manifold tubes.
(11) Remove manifold gaskets.
(12) Remove screws which fastens valve covers (fig. 9, (17)) to tappet
adjustment housings. (See fig. 9, (10) and (35).)
(13) Remove valve covers.
(14) Remove valve cover gaskets. (See fig. 9, (18).)
b. Removing carbon. (1) Use the wire brush (fig. 2, (9)) to remove
the carbon and lead deposits from the combustion chamber of the cylinder
heads.
(2) Turn starter rope pulley to bring pistons (fig. 9, (30)) to the top
position.
(3) Use wire brush to remove deposits from piston heads. (See fig. 9,
(29).)
36
TM 8-630
52
MAINTENANCE INSTRUCTIONS
(4) Turn starter rope pulley to open one of the four valves.
(5) Carefully use the wire brush to remove deposits from the valve and
valve seat. Do not scrape either the valve or the valve seat with a sharp
instrument.
(6) Repeat for each of the three remaining valves.
(7) Use clean cloth to wipe away the loosened carbon.
c. Adjusting valve tappets. (1) Adjust tappets for one cylinder at a
time.
(2) Turn starter rope pulley until the piston is at top dead center of
the compression stroke. The compression stroke can be identified by the
closed position of both valves.
(3) Loosen tappet locking nut. (See fig. 9, (37).)
(4) By turning valve tappet, the clearance between the tappet and the
stem end of the valve (fig. 9, (39)) can be adjusted.
(5) Proper tappet clearances.
(a) Intake valve tappet .006 — .008 inch.
(b) Exhaust valve tappet .008 — .010 inch.
(6) The intake valve can be identified as the valve directly under the
intake port. The intake port does not have cooling fins.
(7) The exhaust valve can be identified as the valve directly under the
exhaust port. (See fig. 9, (1) and (8).) The exhaust port is surrounded by
cooling fins. When separated from the cylinder the exhaust valve can be
identified by a small bore in the center of head and a narrow stem below the
head.
(8) Insert the correct leaf of the feeler gauge (fig. 9, (3)) between the
valve tappet and stem end of valve being adjusted.
(9) Turn tappet until feeler gauge fits snugly. Use end wrenches to
hold tappet and lifter in position and tighten tappet locking nut against the
lifter.
(10) Turn starter rope pulley several times and stop with same piston
at top dead center of the compression stroke.
(11) Recheck tightness of the tappet locking nut.
(12) Recheck the tappet adjustment.
(13) Never file or grind the stem end of the valves.
(14) Repeat preceding steps for each of the valves on both cylinders.
d. Reassembling. (1) Place new valve cover gaskets (fig. 3, (11))
over the valve tappet adjustment housing.
(2) Position valve cover on valve tappet adjustment housing.
(3) Screw in valve cover screws and tighten.
(4) Use new manifold gaskets. (See fig. 3, (9).)
(5) Slip intake manifold adapters over the intake manifold tubes and
line up holes through adapters with those in cylinders.
(6) Screw in and tighten adapter screws.
(7) Use new cylinder head gaskets. (See fig. 3, (6).) Be certain the
gasket surfaces of both the cylinders and heads are clean before putting new
gasket in position.
(8) Position cylinder heads on cylinders.
(9) Screw on cylinder head nuts turning each down to draw head against
the cylinder but do not tighten.
37
TM 8-630
52
X-RAY FIELD UNIT GENERATOR
(D © ©(Ap(pi®lCY v xxM ■ \ \ \ y ^ y / / j® ¥ ■ 4 /^ MAM / '/ / / / & 1 r j ti b JKk\ / . / / w @ 7 IM wy? •/ o ° \S $% rM’M y y / y [ i a / n a \ / \ y ' ^ y 'x^’=====5 7
m . ? x w t 1!@ y y a y y s i M M 4 M \ y \ (JM fflW M ’
©/azM ^ y y ^ \ 'j) ,—Zx\ ff V A I c___ ;_,>. •. n /, ! Wm IIIL r 4; mm xZ VZ- "v- i;
< /WL^
(pj__________ ^r^W* r-p7~z-- yW -Z/ >
"..®' @
I.
2.
3.
4.
5.
6.
7.
8.
9.
10.
II.
12.
13.
14.
15.
Med.
Dept. No.
9R00723
9R00920
9R00727
SR00I5I
SR008I3
9R00723
9R00922
9R00926
9R00924
SR00672
SR003I4
9R00930
Nomenclature
Plug, drain and cover, carburetor.
Washer, drain and cover
plug, carburetor.
Bowl, carburetor.
Bowl to cover gasket carburetor
gasket set,
9R00730.
Washer, lock, screw size
10.
Screw, 10—32 x [/2 inch,
Fill. H.M.
Plug, drain and cover, carburetor.
Cover, carburetor.
Carburetor inlet.
Plate, serial, carburetor.
Nail, metal, serial plate
carburetor.
Nut, 10 x 32, square.
Screw, 10—32 x % inch,
R.H.M.
Carburetor air intake.
Shaft, choke, carburetor.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
Med.
Dept. No.
9R00934
9R00936
9R00932
SR008I6
SR00229
9R00938
9R00940
9R00724
SR008I5
9R00944
9R00942
SROO33O
SR008I4
Nomenclature
Needle, idle jet, carburetor.
Spring, idle jet, carburetor.
Arm, choke, carburetor.
Screw, l/4—28 x I1/, inch,
hex H.M.
Washer, lock, screw, size
'/4.
Body, carburetor.
Arm, throttle, carburetor.
Gasket, carburetor to manifold.
Screw, 10—32 x 9/16 inch,
hex H.M.
Shaft, throttle, carburetor.
Stop, throttle arm, carburetor.
Nut, 10 x 32, hex.
Screw, 10—32 x % inch,
fill. H.M.
Body to bowl gasket of
carburetor gasket set,
9R00730.
Figure 11. Carburetor.
48
TM 8-630
59-61
REPAIR INSTRUCTIONS
(4) Remove only the valve pin, of the valve and seat (fig. 12, (12)).
from cover.
(5) Remove main jet (fig. 12, (8)) from bowl.
(6) Remove metering well plug. (See fig. 12, (1).)
(7) Remove metering well (fig. 12, (3)) from body.
60. CLEANING AND REPLACING PARTS, a. Cleaning. (1) Use compressed
air, if available, or a strand of copper wire, never a needle or steel
wire, to open and clean the passages through the following parts:
(d) Valve seat.
(£) Main jet.
(c) Metering well.
(dj Notch in throttle plate. (See fig. 12, (39).)
(£>) Discharge tube. The discharge tube extends through the body of
the carburetor and the opening is accessible from the under side of the carburetor
body.
(2) Use a cloth soaked with dry cleaning solvent to wipe the interior of
the bowl, float, and the float pin.
b. Inspecting parts. Inspect all disassembled parts for wear, damage,
and incorrect fit with component parts. Check for presence of four cover
screw lock washers and two body to bowl screw lock washers.
c. Replacing parts. (1) Use new body to bowl gasket and bowl to
cover gasket when reassembling carburetor. (See par. 61a.) Both gaskets
are supplied under spare part 9R00730, gaskets, carburetor, set.
(2) Use a new carburetor to manifold gasket when installing carburetor
on engine. (See par. 61b.)
(3) Other parts found to be defective during inspection of parts (b
above) will be replaced with new when reassembling or installing carburetor.
61. REASSEMBLING AND INSTALLING, a. Reassembling. (1) Invert
bowl.
(2) Drop a new metering well upper washer (fig. 12, (5)) in place. Be
certain the old washer has been removed and that the new washer is seated
in the well housing of bowl. \
(3) Insert metering well in well housing.
(4) Put new metering well lower washer (fig. 12, (2)) in place.
(5) Screw in metering well plug.
(6) Invert cover.
(7) Drop valve pin, pointed end first, into valve seat.
(8) Position float (fig. 12, (10)) between cover brackets, being certain
arm of the float will lift the valve.
(9) Insert float pin.
(10) Put a new main jet washer (fig. 12, (7)) in place. Be certain
the old washer has been removed.
(11) Screw main jet into receptacle.
(12) Place new bowl to cover gasket (fig. 12, (9)) on bowl.
(13) Place cover, with float assembled, on bowl.
(14) Place lock washers (fig. 11, (5)) on the four cover screws.
(15) Screw in and evenly tighten four cover screws.
b. Installing. This procedure will be the same when installing the cleaned
and repaired carburetor or a new carburetor. (See fig. 11.)
49
TM 8-630
61
X-RAY FIELD UNIT GENERATOR
I ®
* ® ,
/ 1.11
(ThI J J®
® ~—■**
CT\—----- ><
®” @ ® 0
------ -O / y 1
(G?>)-——- *Ii / ^. "'""^- "'T''''1' ,^. '2. 9
Figure 12. Carburetor parts.
50
TM 8-630
61
REPAIR INSTRUCTIONS
Med.
Dept. No.
I. 9R007I3
2. 9R0072I
3. 9R00722
4. 9R00723
5. 9R00725
6. 9R00727
7. 9R00729
8. 9R007I6
9.
10. 9R00728
II. 9R0073I
12. 9R00720
13. 9R00723
14. 9R00920
15. 9R00922
16. 9R00924
17. 9R00926
18. SR008I8
19. SR00723
20. 9R00928
21. 9R00930
Nomenclature
Plug, metering well, carburetor.
Washer, lower, metering
well, carburetor.
Well, metering, carburetor.
Plug, drain and cover, carburetor.
Washer, upper, metering
well, carburetor.
Bowl, carburetor.
Washer, main jet, carburetor.
Jet, main, carburetor.
Bowl to cover gasket of
carburetor gasket set,
9R00730.
Float, complete.
Pin, float, carburetor.
Valve and seat, carburetor.
Plug, drain and cover, carburetor.
Washer, drain and cover
plug, carburetor.
Cover, carburetor.
Mail, metal, serial plate,
carburetor.
Plate, serial, carburetor.
Screw, 5—40 x 3/16 inch,
R.H.M.
Washer, lock, screw size 5.
Plate, choke, carburetor.
Shaft, choke, carburetor.
Med.
Dept. No. Nomenclature
22. SR003I4 Screw, 10—32 x % inch,
R.H.M.
23. 9R00932 Arm, choke, carburetor.
24. SR00672 Nut, 10 x 32, square.
25. 9R00934 Needle, idle jet, carburetor.
26. 9R00936 Spring, idle jet, carburetor.
27. SR00229 Washer, lock, screw size
'/4.
28. SR008I6 Screw, l/4-28 x 1 inch,
hex H.M.
29. 9R00938 Body, carburetor.
30. SR008I3 Screw, 10—32 x '/z inch,
fill. H.M.
31. 9R00940 Arm, throttle, carburetor.
32. SR008I5 Screw, 10-32 x 9/16 inch,
hex H.M.
33. SR00297 Washer, screw size 1/4.
34. 9R00942 Stop, throttle arm, carburetor.
35. SROO33O Nut, 10 x 32, hex: For
locking throttle adjusting
screw.
36. SR008I4 Screw, 10—32 x % inch,
fill. H.M.: For adjusting
throttle.
37. 9R00944 Shaft, throttle, carburetor.
38. SR008I7 Screw, 5—40 x /4 inch,
O.H.M.
39. 9R00946 Plate, throttle, carburetor.
40. Body to bowl gasket of
carburetor gasket set,
9R00730.
Figure 12. Carburetor parts—Continued,
51
TM 8-630
61-63
X-RAY FIELD UNIT GENERATOR
(1) When installing a new carburetor it is necessary to separate the
bowl from the body.
(2) Use a new carburetor to manifold gasket. (See fig. 11, (23).)
(3) Position carburetor on intake manifold, insert and tighten carburetor
base screws.
(4) Connect manual choke control to choke arm.
(5) Connect throttle linkage to throttle arm.
(6) Use a new body to bowl gasket. (See fig. 12, (40).)
(7) Position bowl on body.
(8) Put lock washers (fig. 12, (27)) on both hex head screws.
(9) Insert screws through body and fasten assembled bowl in place.
(10) Connect carburetor fuel line.
(11) Put air cleaner adapter in place.
(12) Tighten adapter locking screw.
62. ADJUSTING AND TESTING, a. Adjusting. There is no adjustment to
be made within the carburetor. Adjustment and setting of the throttle arm
and stop is covered under governor adjusting and testing. (See par. 77.)
b. Testing. Start engine. (See par. 14.) It will require considerable
cranking to fill the carburetor bowl. Check for leaks, hard starting, and unsteady
operation of engine.
Section XXIV. FUEL PUMP REPAIR
63. GENERAL. This section contains supplemental instructions on the fuel
pump service. (See par. 45.) Carefully read the instructions on fuel supply
system service (sec. XVII) before proceeding with repairs covered in this
section.
a. Models. Model OTC—38 and model OTC—38B are equipped with
different fuel pumps. Both fuel pumps as complete assemblies are interchangeable
between models. The component parts of each fuel pump are not
interchangeable with the other. Instructions contained in this section of the
manual pertain only to the improved fuel pump on model OTC—38B. The
instructions for removing, disassembling, cleaning, and inspection will generally
cover both fuel pumps. If inspection of disassembled parts of the model
OTC—38 fuel pump discloses necessary replacement of component parts the
entire fuel pump assembly should be replaced with the model OTC—38B fuel
pump assembly which is spare part No. 9R00740, fuel pump, complete. Attach
a notation to the unit that this change has been made. All spart parts
supplied are for the model OTC—38B fuel pump only.
b. Spare Part No. 9R00758, Fuel Pump Kit. This kit is assembled to
furnish the parts necessary for a general reconditioning of the fuel pump.
When replacing any part of the fuel pump it is advisable to replace all the
spare parts contained in the kit as a preventive maintenance service to avoid
repeated fuel pump failure. The contents of the kit are illustrated and listed
in figure 13.
52
TM 8-630
63
REPAIR INSTRUCTIONS
^rjSHHgggggK;
@® '? V®
4Rh i i
® ®
\^HB^ / ; Z > ’ ' Med.
Dept. No. Nomenclature
I. 9R00756 Gasket, fuel pump, bowl.
2. 9R00745 Valve, fuel pump.
3. 9R00948 Diaphragm and lever link,
fuel pump.
Figure 13- Fuel pump
Med.
Dept. No. Nomenclature
4. 9R00956 Gasket, valve, fuel
pump.
5. 9R00748 Gasket, fuel pump.
kit. No. 9R00758.
53
TM 8-630
63
X-RAY FIELD UNIT GENERATOR
d’rSrA
'= ' H
// // ' '' ''' ' ft J®
(4;--!~.. . _ 1 
(T) V> n6.@
ri - J|m!
(?y_ L^SlvX n y\ xx\ O Xs- dfl I \/v\ \
^^HfDvDtlD
&''''''''''^^) Section XXV. MAGNETO REPAIR
68. GENERAL. This section contains instructions for the service of the magneto.
Carefully read the instructions on the ignition system service (sec. XVI)
before proceeding with the repairs covered in this section.
69. REMOVING AND DISASSEMBLING, a. Removing. Remove the four
wing nuts (fig. 1, (3)) from base and skid panel studs.
(2) Lift the entire unit from the base and skid panel and place it
on a bench with the engine end of the unit even with the front edge of the
bench.
(3) Remove the four exhaust muffler screws.
(4) Remove the exhaust muffler from the engine.
(5) Insert a socket wrench through the blower housing grill and loosen
the nut in the center of the blower wheel one and one half turns. If necessary
to lock crankshaft by means of the blower fins use the inner edge of a fin and
use extreme care not to damage fins.
(6) Insert a block of hardwood through the grill and against the nut
and give a sharp blow with a hammer to loosen the blower wheel from the
tapered shaft.
(7) Remove the nut.
(8) Remove blower housing screws.
(9) Pull blower housing forward against carrying frame.
(10) Reach inside the housing and disconnect the wires from the stop
buttons. (See fig. 5, (19).) These are spring type connections.
(11) Pull blower wheel off shaft into blower housing.
(12) Turn blower housing counterclockwise about 45° and remove
blower wheel and housing through the bottom of carrying frame.
(13) Use any means available to mark each wire and its respective
terminal. Unscrew and unsolder wires leading from magneto assembly.
(14) Note the arrow near the top of magneto back plate. (See fig. 7,
(5)-) . ... . r ,
(15) Mark the gear case at a point that coincides with the point of the
arrow.
(16) Remove both screws from the slotted holes in the back plate and
remove the magneto assembly.
b. Disassembling. Do not remove the two laminated magneto coil shoes
(fig. 7, (2)) from back plate unless the coils of plates require replacing. Test
coils. (See par. 70b.)
(1) If coil shoes are removed use a sharp steel point to mark their positions
on back plate.
(2) Carefully observe the arrangement of the coil connections and the
positions of the right coil (fig. 7, (3)) and the left coil. (See fig. 7, (4).)
Note that the high tension terminals are about 15/32 inch from the nearest
point on the coil shoes and this spacing serves as a safety gap.
(3) Slip the insulating tube from the connection between the coils.
(4) Unsolder the connection.
(5) Each coil is retained by the bent end of a lamination. Straighten
these ends and remove coils.
57
TM 8-630
70-71
X-RAY FIELD UNIT GENERATOR
70. CLEANING, TESTING, INSPECTING, AND REPLACING PARTS, a.
Cleaning parts. Use a clean cloth, slightly dampened with dry-cleaning solvent
to wipe any oil and dirt from the coil shoes, back plate, and inner side
of blower wheel.
b. Testing coils. (1) Use test meter in Medical Department maintenance
and repair tool set, 9N45705.
(2) Set meter for continuity test.
(3) Connect meter leads to terminal ends of one coil. Meter should
show continuity.
(4) Connect a meter lead to one terminal end of a coil and move other
meter lead about the exterior of the same coil. If meter shows continuity during
this test it indicates faulty external insulation. |
(5) It is possible for the coil to be internally shorted which is cause
lor replacement. This defect is difficult to detect by means of a test meter. /
An internal short would show the coil to have less resistance than the other
and would, if the short is serious, result in too little output to bridge the
spark plug gap during the ignition system test. (See par. 40.)
c. Inspecting disassembled parts. (1) Coil shoes. Inspect for excessive
rust or corrosion.
(2) Wiring. Inspect for frayed or worn insulation.
d. Replacing parts. Parts which are found to be defective will be
replaced with new when reassembling. (See par. 71a.)
71. REASSEMBLING AND INSTALLING, a. Reassembling. (1) Slip
coils on coil shoes. Be careful not to damage the insulation of the coils.
(2) Bend one lamination over the end of each coil to retain it in position.
Again be careful not to damage the coil insulation.
(3) Solder the intercoil wire connection.
(4) Slip insulating tube over the intercoil connecting wire.
(5) If coil shoes have been removed position them exactly as marked
when disassembling.
(6) Insert four screws through shoes and fasten to back plate.
(7) To aid in determining proper connections make use of the wiring
diagram. (See fig. 15.)
b. Installing. (1) Insert both screws through slotted holes of back plate
and screw into taps in gearcase. Do not tighten.
(2) Position back plate until the arrow is exactly in line with the mark
place on the gearcase during disassembly. A
Note. At this point of reassembly any adjustment of timing (par. 12a'), found
to be necessary in previous operation, will be made. d
(3) Tighten both back plate screws securely. *
(4) Solder spark plug cables and stop button wires in position.
(5) Place blower wheel within blower housing and insert both through
the bottom of the carrying frame and turn until in approximate position.
(6) Put blower wheel on shaft.
(7) Snap stop button wires into the spring connectors at each stop
button. । r
(8) Put blower housing in correct position and fasten all blower housing
screws.
(9) Install and tighten nut on shaft of blower wheel. Use a socket
wrench.
58
TM 8-630
71
REPAIR INSTRUCTIONS
MAGNETO--------------------------------
\ ex 'o q_ °-o Jo /
spark vp Cp p ry PLUGS I V ■=■ (ft---------’ , I
------ TV
I*— GAP
MAGNETO IGNITION d MAGNETO BREAKER
CONDENSER ---------------------------------- tM C
LU
STOP O STOP
BUTTON BUTTON p--------_1------------
Figure 15. Ignition system wiring diagram.
59
TM 8-630
71-72
X-RAY FIELD UNIT GENERATOR
(10) Put new muffler gaskets (fig. 3, (9)) in place.
(11) Position exhaust muffler on engine.
(12) Insert and tighten the four exhaust muffler screws.
(13) Replace unit on base and skid panel of carrying case.
(14) Securely tighten the base panel wing nuts.
72. ADJUSTING AND TESTING, a. Adjusting.
Note. Right and left position and clockwise rotation as mentioned in this subparagraph
will be as viewed from the gearcase end of the unit.
(1) Mark exterior of blower wheel, fa) It will be noted that the inner
edge of the blower wheel has two opposing magnets. Each of the magnets has
two surface areas. The blower wheel, when installed, turns counterclockwise
and, using that direction of travel, determines the leading surface of each magnet
and the trailing edge of each surface.
(£) Mark the position of the trailing edge of the leading surface of
each magnet on exterior of blower wheel.
(2) Mark position of magneto core on gearcase, fa) Position back
plate until the arrow is exactly in line with the mark placed on gearcase.
fb) Mark the position of the lower edge of the right coil core on
the exterior of the gearcase.
(3) Positioning breaker points, fa) Place blower wheel key in crankshaft.
fb) Place blower wheel on crankshaft.
fc) Turn blower wheel until the top dead center mark fTC) is in line
with the corresponding line on the gearcase.
fd) Set test meter to indicate continuity.
fe) Connect one test meter lead to the stationary point of the ignition
breaker.
ff) Connect the second test meter lead to the arm of the ignition breaker.
Be certain this connection does not in any way retard or prohibit the movement
of the breaker arm.
fg) Turn the blower wheel clockwise until the meter shows the continuity
broken. Make this adjustment as fine as possible. If the meter needle
is vibrating between a reading and no reading hold the blower wheel in that
position. At this position the ignition breaker points are just opening.
(4) Positioning the back plate, fa) When the breaker points are barely
open, as described above, one mark on the blower wheel should be 1/16 inch
beyond, or below, the mark on the gearcase.
fb) Determine the necessary direction and distance of movement of back
plate.
(c) Remove the blower wheel and make the predetermined adjustment
of the back plate. Tighten the screws which fasten the back plate of the
gearcase.
fd) In this position the maximum spark is developed.
fe) Mark the new position of the back plate on the gearcase.
ff) Continue the installation of magneto. (See par. 71b.)
b. Testing. (1) Coils. Testing of the magneto coil is covered under
replacing of magneto parts. (See par. 70b.)
(2) Ignition system. Follow instructions for testing ignition system.
(See par. 40.)
60
TM 8-630
73-74
REPAIR INSTRUCTIONS
Section XXVI. GOVERNOR AND BOOSTER REPAIR
73. GENERAL, a. This section contains instructions on the repair of the
governor and booster. The existing setting of the governor and booster should
never be changed unless necessary as after a major engine overhaul.
b. Purpose of governor and booster. (1) Governor. The governor maintains
a constant engine speed of 1,800 RPM. This control is accomplished
by means of four weights (tig. 16, (18)) pivoted on a revolving pivot
plate, (fig. 16, (17)) which is fastened to the camshaft gear. When the
engine speed increases, the weights pivot outward and react on a series of
shafts and links which throttle down the engine. If the engine speed decreases,
the weights are pivoted inward by the tension of the governor spring
(fig. 16, (16)) and results in the throttle opening and increasing the engine
speed. This is a constant balancing of engine speeds but it will be noted that
there must be a change in engine speed before the governor functions.
(2) Booster. The booster also maintains a constant engine speed of
1,800 RPM but is on instantaneous electrical action. The booster coil (fig.
16, (6)) is connected in series with one line to the cable outlet. When the
X-ray load is placed on the generator, the current flow through the coil is
increased. This reacts on the throttle linkage and opens the throttle to offset
the drop in engine speed, which results from a load being placed on the
generator. This, therefore, is the purpose of the booster, to open the throttle
wider at the same instant the load is applied to the generator, to avoid, a decrease
in engine speed. If the governor were the only controlling member the
engine speed would decrease momentarily until the governor leveled off the
speed.
74. REMOVING AND DISASSEMBLING, a. Removing governor. (1)
Make a sketch which shows all details of existing adjustment, noting the
number of threads exposed beyond nuts, length and position of arm, and the
spacing between members. Use figure 17 as a guide for the sketch. .
(2) Slip governor spring from spring stud. (See fig. 16, (24).)
(3) Mark position of booster housing (fig. 16, (7)) on booster bracket,
(fig. 16, (25)).
(4) Loosen both screws which fasten booster housing to booster bracket.
(5) Loosen governor arm rod screw.
(6) Pry governor arm rod upward and off shaft of paddle. (See fig.
16, part (15).)
Note. To repair internal mechanism of the governor, it is not necessary to further
disassemble the external linkage and mechanism.
(7) Remove the four wing nuts (fig. 1, (3)) from base and skid
panel (fig. 5, (20)).
(8) Remove both clamp brackets. (See fig. 1, (2).)
(9) Lift the entire unit from the base and skid panel and place it on
a bench with the engine end of the unit even with the front edge of the
bench.
(10) Remove the four exhaust muffler screws.
(11) Remove the exhaust muffler.
(12) Insert a socket wrench through the blower housing grill and loosen
nut in the center of blower wheel one and one half turns. If necessary to
61
TM 8-630
74
X-RAY FIELD UNIT GENERATOR
\z )
® ® ® —x 4 n
// / © I
s ®X-Z^ £^^^Wk!'?/WHP I JX® r0 ^ 4 1M6 ^ l Jj?W
(Ty- - g y J ^ P @
® C O ^ ^ lA® ) Have bent end of throttle control rod in position to connect into
the carburetor throttle arm.
(3) Connect throttle control rod to carburetor throttle arm.
(4) Bend throttle control rod cotter pin in place.
(5) Place booster housing on booster bracket at the previously marked
position. (See par. 74c.)
(6) Insert both booster housing screws and tighten housing in correct
position on bracket.
(7) For final adjustment follow the instructions on governor and booster
adjustment. (See par. 77.)
77. ADJUSTING AND TESTING, a. Adjusting. Do not change any existing
adjustments unless made necessary by complete disassembly of carburetor,
booster or governor.
(1) Setting carburetor throttle arm and stop. These are approximate settings
and may require slight changes after testing. (See b below.)
() Loosen throttle arm adjusting screw lock nut. (See fig. 17, (1).)
(c) Turn out throttle arm stop adjusting screw (fig. 17, (2)) until it
is entirely within the throttle arm stop.
() Turn spring stud until the position of the spring (fig. 17, (11))
hook on the stud is % inch from the center of the slotted end of governor
paddle shaft (fig. 17, (14)) as shown in figure 17.
(c) Tighten spring stud lock nut.
( / 1 H \ Iff-----® IY&\\ v )) v ^■^YVrZ/w/// W] )W
®—z @1 @ ® ®Jl Y@Y —®
Med.
Dept. No. Nomenclature
I.
2.
3.
4.
5.
6.
7.
8.
9.
9R00866
9R00604
9R006I0
9R006I2
9R00627
9R00628
9R00606
9R007II
9R0I000
9R00700
9R00960
10.
II.
9R0070I
9R00702
Shaft and paddle, governor.
Cylinder, C.I., 2% inch,
L/H.
Head, cylinder, L/H.
Gasket, cylinder head.
Cover, valve.
Gasket, valve cover.
Gasket, cylinder base.
Crankcase: For model 38B
(illustrated).
Crankcase: For model 38.
Crankcase, with bearing
plate assembly: For model
38B (illustrated).
Crankcase, with bearing
plate assembly: For model
38.
Bearing plate and generator
support.
Gasket, bearing plate and
generator support.
Med.
Dept. No. Nomenclature
12. 9R00602 Cylinder, C.I., 2% inch,
R/H.
13. 9R00608 Head, cylinder, R/H.
14. 9R00706 Plug, oil.
15. SR0045I Coupling, pipe, % inch.
16. SR002I5 Nipple, close, pipe, %
inch: For oil drain.
17. 9R00705 Gasket, oil base
18. 9R00704 Base, oil.
19. 9R00698 Gasket, oil pump: For
model 38B.
20. 9R00689 Cover, oil pump: For
model 38B.
21. 9R007I0 Gasket, gearcase: For
model 38B (illustrated).
9R00964 Gasket, gearcase: For
model 38.
22. 9R00708 Gearcase: For model 38B
(illustrated).
9R00962 Gearcase, aluminum: For
model 38.
Figure 18. Engine assembly, structural parts.
74
TM 8-630
80
REPAIR INSTRUCTIONS
® A® ® ® ® ® ®
®(Z--—---------X ' MMP
®------------\Xx\ @®@ j®
®®—wt ¥ Cw^A®M1 Myy>!y
(® -----—^7®
Med,
Dept. No. Nomenclature
1. 9R00837 Nut, drive gear, oil pump.
2. 9R00693 Gear, drive, oil pump.
3. 9R00682 Nut, crankshaft.
4. 9R00680 Gear, crankshaft.
5. 9R00660 Gear, crankshaft.
6. 9R00659 Washer, spacer, camshaft
gear.
7. 9R00678 Bearing, crankshaft.
8. 9R00656 Bearing, camshaft, front.
9. 9R006I6 Valve, exhaust.
10. 9R006I4 Valve, intake.
II. 9R00625 Insert, valve seat.
12. 9R00624 Pin, valve.
13. 9R006I8 Guidej valve.
14. 9R00620 Springs, valve.
15. 9R00626 Washer, valve.
16. 9R00623 Lifter, valve: With tappet,
9R00622.
17. 9R00654 Camshaft.
18. 9R00678 Bearing, crankcase.
19. 9R00658 Bearing, camshaft, rear.
20. 9R00676 Seal, oil, crankshaft.
21. 9R0064I Insert, rod, connecting
bearing.
22. 9R00640 Rod, connecting, complete.
23. 9R00639 Bushing, piston pin.
Med.
Dept. No. Nomenclature
24. 9R00630 Piston, 2% inch bore.
25. 9R00629 Pin, piston.
26. 9R00638 Ring, lock, piston pin.
27. Oil ring of piston ring set,
9R00632.
28. Compression ring of piston
ring set, 9R00632.
29. 9R00687 Valve, relief, oil pump.
30. 9R00696 Screen, oil pump.
31. 9R00637 Washer, connecting rod
screw.
32. SR00809 Screw, I/4—28 x 1 inch hex
head, cap: For connecting
rod.
33. 9R00674 Crankshaft.
34. 9R00685 Body and idlershaft, oil
pump.
35. SR00664 Nipple, long, pipe, /g inch
x 2'/8 inch.
36. 9R00697 Cup, intake, oil pump.
37. 9R00683 Ring, screen lock, oil
pump.
38. 9R0069I Gear and shaft, body
driver, oil pump.
39. 9R00695 Gear, idler, oil pump.
Figure 19. Engine assembly, junctional parts.
75
TM 8-630
80
X-RAY FIELD UNIT GENERATOR
(11) Remove nuts from the five cylinder to crankcase studs for each
cylinder, including the studs which enter the valve tappet adjustment housings.
(12) Remove both cylinder. Use care not to damage the cylinder bore
or pistons.
(13) Remove cylinder base gaskets. (See fig. 18, (7).)
e. Remove valves and valve lifters. (1) Place cylinder on bench with
studs down.
(2) Use a piece of wood to block each valve head in closed or nearly
closed position. Use any means to keep valves (fig. 19, (9) and (10)) from
moving out of cylinder, or opening, when valve springs are compressed.
(3) Compress valve spring (fig. 19, (14)) and valve washer (fig. 19,
(15)) to expose the valve pin (fig. 19, (12)). Hold springs in compressed
position.
(4) Remove valve pin.
(5) Release valve spring.-
(6) Remove valve from cylinder. Use some means to mark valve so
it will be replaced in same cylinder.
(7) Remove valve washer and spring from tappet adjustment housing.
(8) Repeat same operation for the remaining three valves.
(9) Remove valve lifters from crankcase. Use some means to mark
lifters so they are replaced in original position in crankcase.
f. Remove gearcase. (1) Loosen blower wheel nut.
(2) Place a block of hard wood aaginst blower wheel nut and strike it
a sharp blow with a heavy hammer.
(3) Remove blower wheel nut from crankshaft.
(4) Remove blower wheel. Do not lose the key.
(5) Remove four screws which fasten the gearcase (fig. 18, (22)) to
the crankcase.
(6) Remove gearcase. Do not remove the governor arm rod from the
governor shaft and paddle. (See fig. 18, (1)-)
(7) Remove gearcase gasket. (See fig. 18, (21).)
g. Remove gearcase oil seal. (1) Remove cork oil seal from gearcase.
(2) Scrape recess clean.
(3) Replace a new oil seal when reassembling engine. ‘ (See par. 93.)
h. Check gear clearance. (1) Clearance or backlash between crankshaft
gear (fig. 19, (4)) and camshaft gear (fig. 19, (5)) should be .002
inch to .005 inch.
(2) Check. Correct clearance will permit the passage of a single thickness
of ordinary newspaper through the gear mesh but will not pass a piece
of heavy wrapping paper.
(3) If clearance is too great replace both the crankshaft gear and the
camshaft gear when reassembling engine. (See par. 93.)
i. Remove crankshaft gear. (1) Remove crankshaft nut.
(2) Remove crankshaft gear. (See fig. 19, (4).)
j. Remove oil base. (1) Remove nuts from the four oil bases to crankcase
studs.
(2) Lift crankcase assembly (fig. 18, (9)) from oil base (fig. 18, (18)).
(3) Remove oil plug (fig. 18, (14)) and drain oil from base.
(4) Remove oil base gasket. (See fig. 18, (17).)
76
TM 8-630
80-81
REPAIR INSTRUCTIONS
k. Remove oil pump on model OTC-38. (1) Remove both oil lines.
(2) Remove the screw which fastens oil pump body to right side of
crankcase.
(3) Remove oil pump and pusher rod from crankcase.
I. Remove oil pump on model OTC—38B. (1) Remove oil pump intake
cup (fig. 19, (36)) from oil pump body (fig. 19, (34)).
(2) Remove both hex head bolts which fasten oil pump cover (fig. 18,
(20)) to crankcase.
(3) Remove pump body through front of crankcase.
m. Remove pistons. (1) Remove both connecting rod cap screws. (See
fig. 19, (32).)
(2) Remove lower connecting rod cap.
(3) Remove piston and rod from crankcase.
(4) Replace cap on rod to keep each rod complete with original parts.
(5) Mark rod and piston in some manner so that they will be replaced
in original cylinder when reassembling engine.
(6) Repeat process for opposite piston and rod.
(7) Remove piston pin lock ring (fig. 19, (26)) from piston (fig. 19,
(24)).
(8) Remove piston pin (fig. 19, (25)) from piston.
(9) Separate connecting rod (fig. 19, (22)) from piston.
(10) Remove the compression rings (fig. 19, (28)) and oil ring (fig.
19, (27)) from piston. Rings should be replaced with new ones when reassembling
engine. (See par. 93.) Spare part 9R00632, rings, piston, set, contains
two compression rings and one oil ring. Always requisition two sets of
9R00632 to replace rings on both pistons.
n. Remove bearing plate and generator support. (1) Remove the six
screws which fasten the rear bearing plate and generator support (fig. 18,
(10)) to crankcase.
(2) Remove bearing plate and generator support from crankcase.
(3) Remove bearing plate and generator support gasket. (See fig. 18,
(11)-)
o. Remove crankshaft oil seal. (1) Pull crankshaft oil seal (fig. 19,
(20)) from the bearing plate and generator support.
(2) Replace with a new oil seal when reassembling engine. (See par.
93.)
p. Remove crankshaft and camshaft. (1) Remove crankshaft through
rear of crankcase.
(2) Remove camshaft (fig. 19, (17)), with gear (fig. 19, (5)) inplace,
through front of crankcase.
81. SERVICING OIL PUMP ON MODEL OTC-38. a. Disassembling. (1)
Remove push rod (See fig. 20, (8).)
(2) Remove plunger (fig. 20, (4)) from oil pump body (fig. 20, (1)).
(3) Remove plunger spring (fig. 20, (9)) from oil pump body.
(4) Remove inlet check ball from body.
(5) Remove cleaning plug from body.
(6) Remove outlet check ball through cleaning plug opening.
(7) Remove screen. (See fig. 20, (11).)
77
TM 8-630
81
X-RAY FIELD UNIT GENERATOR
(7)---------
®---
(£)------________________-(p)
®—®—®
Med.
Dept. No. Nomenclature
I. 9R00977 Body, oil pump.
2. 9R00992 Valve, relief, oil pump,
complete.
3. 9R00974 Line, oil, front bearing.
4. 9R00980 Plunger, oil pump.
5. 9R00958 Camshaft.
6. 9R00986 Shaft, cam follower arm,
oil pump.
Med.
Dept. No. Nomenclature
7. 9R00984
8. 9R00988
9. 9R00982
10. 9R00976
II. 9R00972
Arm, cam follower, oil
pump.
Rod, push, oil pump.
Spring, plunger, oil pump.
Line, oil, rear bearing.
Screen, oil pump.
Figure 20. Oil pump assembly on model OTC-38.
78
TM 8-630
81-82
REPAIR INSTRUCTIONS
l
(8) Remove complete oil pump relief valve. (See fig. 20, (2).) Do not
disassemble the valve. If inspection of engine indicates the relief valve is
releasing oil at too low or too high a pressure, replace the entire relief valve
assembly.
b. Cleaning. (1) Submerge all disassembled oil pump parts, including
both oil lines, in dry-cleaning solvent. Allow the parts to soak for approximately
30 minutes.
(2) Insert a copper wire through both oil lines to remove any restrictions.
(3) Rinse the oil pump, parts in clean dry-cleaning solvent.
(4) Pour dry-cleaning solvent from oil pump body by turning body in
all directions to empty the internal passages.
(5) Plunger spring and screen may require additional cleaning with a
bristle brush, such as an old tooth brush, and dry-cleaning solvent.
c. Inspecting. (1) Plunger spring. Inspect for broken spring. If broken,
replace with new spring during reassembly.
(2) Ball check seats. Hold pump body to light or use a flashlight to
inspect ball check seats for foreign matter.
(3) Screen. Inspect screen for cleanliness and see that the screen is not
punctured. If screen is punctured, replace with new screen during reassembly.
(4) Oil lines. Pour dry-cleaning solvent through each line to determine
that it is open.
(5) Cam follower arm. Inspect cam follower arm (fig. 20, (7)) for
freedom of action on the shaft (fig. 20, (6)).
(6) Complete inspection for operation after partial reassembly. (See
par. 81d.)
d. Reassembling. (1) Screw pressure relief valve into pump body.
(2) Place screen in position under base of pump body. Screen may be
spread slightly to make it hold in base.
(3) Give outlet check ball a final inspection for cleanliness. Drop outlet
check ball through the cleaning plug opening of the pump body into place.
(4) Screw cleaning plug into pump body.
(5) Give inlet check ball a final inspection for cleanliness. Drop the
inlet check ball through the cylinder of pump into its place.
(6) Place plunger spring into pump cylinder.
(7) Place plunger with smallest section down into pump cylinder.
e. Operational inspection of oil pump. (1) Temporarily connect both
oil lines to the pump pipe tee.
(2) Place the assembled oil pump in a clean, small, shallow container.
(3) Pour oil, engine, into the container until the base only of the oil
pump body is covered.
(4) Alternately depress and release the plunger. Oil should be ejected
from the oil lines. Be certain oil is being ejected from both lines.
82. SERVICING OIL PUMP ON MODEL OTC-38B. a. Disassembling.
(1) Remove nut (fig. 19, (1)) from drive gear.
(2) Remove drive gear. (See fig. 19, (2).)
(3) Remove both bolts which fasten oil pump body (fig. 19 (34)3 to
oil pump cover.
(4) Remove body from cover.
(5) Remove gasket (fig. 18, (19)) from cover.
(6) Remove body driver gear and shaft (fig. 19, (38)) from body.
79
TM 8-630
82-84
X-RAY FIELD UNIT GENERATOR
(7) Remove idler gear (fig. 19, (39)) from body.
(8) Remove screen lock ring (fig. 19, (37)) from intake cup.
(9) Remove screen (fig. 19, (30).)
(10) Do not remove or disassemble the oil pump pressure relief valve.
(See fig. 19, (29).) If inspection of engine parts indicates the relief valve
is releasing oil at too low or too high a pressure, replace it with a new relief
valve.
b. Cleaning. (1) Submerge all disassembled oil pump parts in drycleaning
solvent. Allow parts to soak for approximately 30 minutes.
(2) Rinse the oil pump parts in clean dry-cleaning solvent.
(3) Screen may require additional cleaning with a bristle brush, such
as an old tooth brush, and dry-cleaning solvent.
c. Inspecting. (1) Driver and idler gears. Inspect for chipped or marred
teeth. If either gear is defective, replace oil pump with new complete oil
pump assembly, 9R00694, when reassembling engine. (See par. 93e.)
(2) Body. Inspect for scratched or grooved inner surfaces. If damaged,
replace with new complete oil pump assembly, 9R00694, when reassembling
engine. (See par. 93e.)
(3) Screen. Inspect screen to see that it is clean and not punctured. If
punctured, replace with new screen when reassembling oil pump. (See d
below.)
d. Reassembling. (1) Place screen in oil pump intake cup.
(2) Fasten screen lock ring in place.
(3) Position idler gear on shaft of pump body.
(4) Position body driver gear in body.
(5) Put new gasket (fig. 18, (19)) in place on pump cover.
(6) Position pump cover over pump body with gears in place.
(7) Insert and tighten both bolts which fasten body to cover.
(8) Place drive gear on body driver gear shaft extending through cover.
(9) Screw nut on body driver gear shaft to hold drive gear in place.
Spin drive gear to see that the gears are turning freely.
83. CLEANING AND INSPECTING CYLINDER HEADS, a. Cleaning.
(1) Remove carbon deposits from heads.
(2) Thoroughly clean cooling fins.
(3) Clean gasket surfaces.
b. Inspecting. (1) Visually inspect heads for cracks. A cracked head
would have been detected during operation by a hissing sound. If head is
cracked, replace it with a new head (fig. 18, (3) or (13)) when reassembling
engine. (See par. 93o.)
(2) Place heads on a perfectly flat surface. If head can be rocked, it is
warped.
(3) Replace defective heads with new cylinder heads when reassembling
engine. (See par. 93o.)
84. CLEANING AND INSPECTING CYLINDERS, a. Cleaning. (1) Clean
any carbon deposit from top of cylinder bore.
(2) Clean exhaust and intake ports. Be certain to wipe any loose carbon
from the interior of the ports.
(3) Clean cooling fins.
(4) Clean gasket surfaces.
80
TM 8-630
84-87
REPAIR INSTRUCTIONS
b. Inspecting. (1) Inspect for cracks.
(2) Inspect bore for scored or scarred condition.
(3) Inspect bore for ring ridge. A ridge around the top of the cylinder
bore might also indicate excessive out of round or tapered bore.
(4) Replace defective cylinders with new cylinders (fig. 18, (2) and
(12)) when reassembling engine. (See par. 93h.) It is advisable to use new
pistons and piston rings with new cylinders. Cylinders are supplied with
valve seats installed which necessitates grinding the valves (par. 92) to the
new seats.
85. CLEANING AND INSPECTING CRANKCASE, a. Cleaning. (1)
Clean crankcase (fig. 18, (8)) and bearing plate (fig. 18, (10)) with drycleaning
solvent.
(2) Run a copper wire through the oil passages of the model OTC-38B
crankcase. Follow with compressed air if available.
(3) Clean gasket surfaces of crankcase and bearing plate.
b. Inspecting. (1) Inspect crankcase and bearing plate for cracks.
(2) Inspect both camshaft bearings and the front crankshaft bearing for
scored, scarred, checked, or chipped condition. See that the bearings fit tightly
in the crankcase and that the bearing oil holes are in line with the oil passages
of the crankcase (model OTC-38B).
(3) Inspect the rear crankshaft bearing for scored, scarred, checked, or
chipped condition. See that the bearing fits tightly in the bearing plate.
(4) If any bearing surface is defective, be certain to inspect the respective
journal for damage.
(5) Any defect of the crankcase, bearing; plate or bearing surface will necessitate
replacing both the crankcase and bearing plate if tools and equipment
are not available to remove old bearings and press in new bearings and to line
ream the new bearings. The crankcase and bearing plate (fig. 18, (9)) are
supplied as an assembly with bearings installed.
86. CLEANING AND INSPECTING OIL BASE. a. Cleaning. Thoroughly
clean the oil base with dry-cleaning solvent. Clean gasket surface.
b. Inspecting. (1) Inspect for cracks or holes.
(2) Repair. Use means necessary to correct any defects in oil base.
87. CLEANING AND INSPECTING PISTONS, a. Cleaning. (1) Use a
wire brush to remove the carbon from the piston head and the piston ring
grooves.
(2) Thoroughly clean pistons with dry-cleaning solvent.
b. Inspecting. (1) Inspect for cracks in pistons.
(2) Inspect for scored condition of the piston exterior.
(3) Inspect to see that oil return holes in piston are open.
(4) Replace defective pistons with new pistons (fig. 19, (24)) when reassembling
the engine. (See par. 93i.)
(5) Replace piston rings with a new set when reassembling engine. (See
par. 93i.) This will prevent the possibility of ring failure before the next
major overhaul.
81
TM 8-630
88-91
X-RAY FIELD UNIT GENERATOR
88. CLEANING AND INSPECTING CONNECTING RODS. a. Cleaning.
Clean connecting rod exterior and bearings thoroughly with dry-cleaning
solvent.
b. Inspecting. (1) Inspect bearing surfaces for scored, grooved, burned,
chipped, or checked condition.
(2) Inspect the journal or piston pin of the bearing found to be defective.
(3) Replace the connecting rod with a new complete connecting rod assembly
(fig. 19, (22)) if either bearing is defective.
89. CLEANING AND INSPECTING CRANKSHAFT, a. Cleaning. (1)
Clean exterior of crankshaft.
(2) Run a copper wire through the crankshaft oil passages. Follow
with compressed air if available.
b. Inspecting. (1) Inspect for flaws or cracks in crankshaft.
(2) Inspect main bearing and connecting rod journals for scored,
grooved, burned, chipped, or checked condition.
(3) Also inspect the bearing surface of any defective journal for damage.
(4) Replace the crankshaft with a new crankshaft (fig. 19, (33), if any
journal is damaged, when reassembling the engine. (See par. 93a.)
90. CLEANING AND INSPECTING CAMSHAFT, a. Cleaning. Clean
camshaft and journals with dry-cleaning solvent.
b. Inspecting. (1) Inspect for excessive wear of cams and for scored,
grooved, or burned condition of journals.
(2) Replace camshaft with a new camshaft (fig. 19, (17)), if inspection
has revealed the original to be defective, when reassembling engine. (See
par. 93a.) If new camshaft is installed, remove the camshaft gear (fig. 19,
(5)) from the old camshaft and install it on the new.
91. CLEANING AND INSPECTING VALVES, a. Cleaning. (1) Clean
valve heads and stems.
(2) Clean valve guides in cylinders.
(3) Clean valve lifters.
(4) Keep valves separate so they will be installed in original seats when
reassembling the engine. The exhaust valve (fig. 19, (9)) can be identified
by the narrow stem just below the head and by the small cup in the center
of the head.
b. Inspecting. (1) Valves, (d) Try fit of valve stem in valve guide.
It should move easily in the directions of operation but there should be no side
phy.
(£) Inspect stem for excessive wear or scoring.
(c ) Inspect valve face. If pitted or burned, determine if valve can be
ground (par. 92) or if it must be replaced. If new valve is installed, it must
be ground to seat.
(2) Springs, (d) Inspect for broken springs.
(6) Replace with new springs (fig. 19, (14)), if original are defective,
when reassembling engine. (See par. 93g.)
(3) Seats, (d) Inspect for badly worn or burned valve seats. Determine
if scats are to be ground or replaced with new seats.
82
TM 8-630
91-93
REPAIR INSTRUCTIONS
(Jo) Grind seats by following instructions for valve grinding. (See
par. 92.)
(c) Seats cannot be replaced with the normally available tools and equipment.
The entire crankcase will have to be replaced and the valves ground to
seat properly. (See par. 92.)
(4) Pins, (a) Inspect pins for flattened surfaces or bent condition.
(Jo) Replace with new pins (fig. 19, (2)) if original pins are defective.
(5) Washers. (a) Inspect for bent or grooved flanges.
(Jo) Replace with new washers (fig. 19, (15)) if originals are defective.
(6) Tappets. Inspect for signs of valve stem impression. This condition
makes it impossible to correctly adjust the valve tappet clearance.
(7) Lifters, (a) Inspect for wear or scoring.
(b) Inspect camshaft end of lifter for excessive wear.
(c) Inspect valve lifter ports in crankcase wall for wear and scoring.
See that the cylinders are thoroughly cleaned.
(d) Try fit of lifters in crankcase. Lifters should move easily but there
should be very little side play.
(e) Replace lifters with new valve lifters (fig. 19, (16)) if originals are
defective.
(/) If valve lifter cylinders in crankcase walls are seriously enlarged,
the entire crankcase (fig. 18, (9)) will require replacement.
92. GRINDING VALVES, a. Coat valve face and seat with compound, valve
grinding, medium grade.
b. Insert valve in its original guide.
c. Turn the valve against the seat. Turn it back and forth within a quarter
turn several times. Then turn the valve a quarter turn to a new position and
repeat. Continue this process as long as is necessary to produce a bright band
with a uniform width of 1/16 inch on the valve face and valve seat.
d. Carefully clean grinding compound from valves and seats.
93. REASSEMBLING, a. Install camshaft and crankshaft. (1) Place camshaft,
with cam gear attached, in position in crankcase.
(2) Insert crankshaft through rear of crankcase until front bearing journal
is in place in the front bearing of the crankcase.
b. Replace crankshaft oil seal. (1) Place a new crankshaft oil seal
(fig. 19, (20)) in the bearing plate.
(2) Tap seal into the bearing cap evenly.
(3) Paint outer edge of seal with varnish, shellac, white. Be certain there
is no varnish on the surface of the seat where it will come in contact with
crankshaft.
c. Install bearing place and generator support. (1) Put a new bearing
plate and generator support gasket (fig. 18, (11)) in place on crankcase.
(2) Position bearing plate and generator support on crankcase. Use care
not to damage the oil seal (fig. 19, (20)) when bringing the crankshaft
journal into position in the rear bearing. Check to see that the bearing plate
and generator support gasket has remained in correct position.
(3) Insert and draw up the six screws which fasten the bearing plate
and generator support to the crankcase. Tighten each screw one quarter turn
at a time until all are secure.
83
TM 8-630
93
X-RAY FIELD UNIT GENERATOR
d. Install oil pump on model OTC—38. (1) Place pusher rod in its
receptacle in the oil pump plunger.
(2) Move oil pump assembly and pusher rod into position within the
crankcase. Guide the pusher rod into the cup of the cam follower.
(3) Insert and tighten the screw which fastens the oil pump to the crankcase.
(4) Fasten the oil lines to the fittings in the bearings and oil pump.
e. Install oil pump on model OTC-38B. (1) Position assembled pump
body on crankcase. See that the gasket is not folded or creased.
(2) Insert and tighten both bolts which fasten oil pump to crankcase.
(3) Replace oil pump intake cup on pump body.
f. Install crankshaft gear. (1) Position crankshaft gear so that the timing
mark is adjacent to the timing mark on the camshaft gear.
(2) Put crankshaft gear key in place.
(3) Turn crankshaft until key is in line with the key slot of the crankshaft
gear.
(4) Press gear on crankshaft.
(5) Screw the crankshaft nut into position.
g. Install valves. (1) Insert valve into guide. Replace each valve in
its original guide (if original parts are being installed).
(2) Position valve spring on valve stem.
(3) Place washer on spring.
(4) Compress valve spring and washer and insert valve pin into stem.
Release spring.
(5) Repeat procedure for remaining three valves.
h. Install cylinders. (1) Place valve lifters in their original position in
crankcase.
(2) Place new cylinder base gaskets (fig. 18, (7)) on crankcase.
(3) Position cylinders on cylinder studs.
(4) Screw on and tighten the five stud nuts of each cylinder.
i. Reassemble pistons. (1) Gap piston rings, (a) Place ring in its
respective cylinder bore. Square it with cylinder top and about 1 inch from
top.
(&) Gap between ring ends should be .010 inch. File ring ends until
a .010 inch gap is obtained.
(c) Repeat procedure for each ring, checking it in the cylinder it will
be assembled in.
(2) Place rings on pistons, (a) Check rings for side marked "TOP.”
The "TOP” side will be placed nearest the piston head.
(&) Place oil ring (fig. 19, (27)) in the lower groove of piston.
(c) Place compression rings (fig. 19, (28)) in the remaining grooves of
piston.
(<7) Test to see that the rings move freely around the piston groove.
(3) Install connecting rods in pistons, (a) Use original piston and connecting
rod combination, if new parts are not installed.
(Z>) Position rod in piston.
(c) Insert piston pin.
( 1
WINDING [ ( _ ) 1
^=;—prr ■st GROUND TERMINAL
ON GENERATOR X
GROUND ROD
>4^ pt>
a|pf
Figure 21. Generator wiring diagram.
90
TM 8-630
101-103
REPAIR INSTRUCTIONS
b. Test DC winding of armature. (1) Place one test meter lead on commutator
and the other on commutator shaft.
(2) Reading, (a) Meter should not indicate continuity.
(£) If meter does indicate continuity the armature is grounded to shaft.
Replace with a new armature (fig. 10, (25)) when reassembling generator.
(See par. 103.)
c. Test AC winding of armature. (1) Place one test meter lead on one
slip ring and the other lead on the second slip ring.
(2) Reading, (a) Test meter should indicate continuity.
(b) If test meter does not indicate continuity the AC winding is open
Replace the armature when reassembling generator.
(3) Place one test meter lead on the armature shaft and the other alternately
on each of the slip rings.
(4) Reading, (a) Meter should not indicate continuity.
(A) If meter does indicate continuity the AC winding is grounded to
armature shaft. Replace the armature when reassembling generator.
d. Test field coils for open circuit. (1) Connect one test meter lead on
either field coil lead. Place other meter lead on the second lead from field
coil.
(2) Reading, (a) Meter should indicate continuity.
(b) If meter does not indicate continuity the field coil set is open. Inspect
for loose or broken leads. If break is within field coils, replace with
new field coil set. (See fig. 10, (1).)
e. Test field coils for grounding. (1) Connect one test meter lead to
either field coil lead. Place other meter lead on generator frame.
(2) Readings, (a) Meter should not indicate continuity.
(b) If meter indicates continuity the field coils are grounded to generator
frame. Replace with new field coil set when reassembling generator.
102. UNDERCUTTING COMMUTATOR, a. Tool. Grind the cutting edge
of a hack saw blade to the same width as the mica strips. Also grind one end
to a point.
b. Procedure. Cut each mica strip until it is 1/32 inch below the surface
of the commutator bars.
c. Clean commutator. After undercutting mica be certain to wipe
away all mica dust with a clean dry cloth.
103. REASSEMBLING, a. Install brush rig. (1) Check that ail brushes
are in the raised position, that is, not extending beyond the inner ends of
the brush holders.
(2) Place brush rig within end ball housing. Be certain the yellow indicating
mark on edge of brush rig is in line with the matching mark on
the inner side of the bell housing.
(3) Insert and tighten the four screws which fasten brush rig to end
bell housing. Again check to see that the yellow marks are in line.
b. Installing new field coil set. If inspection revealed the field coil set to
be open or shorted install a new set as follows:
(1) Note the position of old field coil set in generator frame. Install
the new set in the same position.
(2) Remove the three screws holding each of the four pole shoes to the
generator frame.
91
TM 8-630
103-104
X-RAY FIELD UNIT GENERATOR
(3) Remove four pole shoes.
(4) Remove old field coil set from frame.
(5) Position new field coil set (fig. 10, (1)) in generator frame.
(6) Position pole shoes in generator frame.
(7) Insert and tighten screws which fasten pole shoes to frame. Be
certain the pole shoes fit flush against the inside of frame and that the screws
are secure.
c. Install generator on engine, hollow instructions in paragraph 93q.
d. Install conductor cable outlet. (1) Position outlet on generator
frame.
(2) Insert and tighten screws which fasten outlet to frame.
e. Mount unit on carrying frame and base. Follow instructions in
paragraph 93r.
104. TESTING GENERATOR OUTPUT. Follow instruction in paragraph 77b.
92
TM 8-630
1-2
APPENDIX
Section I. SHIPMENT AND STORAGE
I. GENERAL Instructions in this section of the manual cover the preparation
for temporary storage or domestic shipment. Items to be prepared for
temporary storage or domestic shipment are those ready for immediate service
but not used for less than 30 days. These instructions cover only the preparation
of the item. Packaging, crating, and method of shipment will be in accordance
with existing Medical Department procedure. For detailed information
on preparation for indefinite storage, see AR 850—18.
2. PREPARATION FOR TEMPORARY STORAGE AND DOMESTIC SHIPMENT.
a. Lubrication. Lubricate unit completely according to WD Lubrication
Order 5001. (See fig. 6.)
b. Running test. (1) Operate engine for at least 30 minutes. Follow
instructions for running test. (See par. 33, items 1 through 14.)
(2) Correct any defects noted during test or note corrections to be made
on a tag and attach it to the choke control.
c. Fuel in tank. It is not necessary to remove the fuel from the tank
for shipment within the United States, nor to label the tank under Interstate
Commerce Commission Regulation. Leave fuel in the tank, except when storing
in location where fire ordinances or other local regulations require removal
of all gasoline before storage.
d. Exterior of unit. (1) Remove rust appearing on any surface of the
unit by sanding with paper, flint, No. 2.
(2) Place tools, spare parts, and conductor cable within the lid panel.
e. Inspection. (1) Make a systematic inspection to insure that all above
steps have been covered and that the unit is ready for operation on call.
(2) Make a list of all damaged items and attach it to the unit.
f. Engine. (1) Remove air cleaner adapter from carburetor.
(2) Start engine.
(3) Pour, through the carburetor intake, 1/8 pint of oil, lubricating,
preservative, medium (PM).
(4) Immediately press the stop button and hold down until engine stops.
(5) Keep stop button depressed and turn the engine, using the starter
rope, for four or five complete revolutions.
g. Carrying case. Install panels and snap fasteners in place. Any over
packing, crating, and marking will be as directed by storage or shipping
officers.
93
TM 8-630
3-7
X-RAY FIELD UNIT GENERATOR
Section II. REFERENCES
3. ARMY REGULATIONS.
Motor vehicles AR 850—15
Storage of Motor Vehicle Equipment ..................................AR 850-18
Precautions in Handling Gasoline........................................ AR 850—20
4. FIELD AND TECHNICAL MANUALS.
Camouflage Basic Principles .....................................................FM 5-20
Defense against Chemical Attack ............................................FM 21—40
Electrical Fundamentals ...........................................................TM 1—455
Decontamination ........................................................................TM 3—220
Cleaning, Preserving, Seating, Lubricating, and Related
Materials Issued for Ordnance Materiel .........................TM 9—850
Motor Vehicle Inspections and Preventive
Maintenance Services .......................................................TM 9-2810
Fuels and Carburetion.............................................................. TM 10-550
Basic Maintenance Manual .................................................... TM 38—250
5. ARMY SERVICE FORCES MEDICAL SUPPLY CATALOG.
Introduction .......................................................................... Med 1
Index ................................................................................................... Med 2
List of items for troop issue..............................................................Med 3
Organizational and higher-echelon spare parts................................Med 7
List for 9606000 X-ray field unit,
generator (when published).
List of common parts (when published).
List for 9N45705 Medical Department maintenance
and repair tool kit (when published).
List of all parts (SNL) ................................................................... Med 9
List for 9606000 X-ray field unit, generator
(when published).
6. LIST OF FORMS MENTIONED IN MANUAL.
WD Form 48, Drivers Trip Ticket and Preventive Maintenance Service
Record.
WD, AGO Form 461, Work Sheet for Wheeled and Half-track Vehicles.
WD, AGO Form 468, Unsatisfactory Equipment Report.
7. LIST OF ABBREVIATIONS USED
AC.................. Alternating current
AGO ... Adjutant General’s Office
ASF .............. Army Service Forces
DC ........................... Direct current
fig......................................... figure
No........................................Number
IN MANUAL.
par.................................... paragraph
RPM ........ Revolutions per minute
sec.......................................... section
SNL... Standard Nomenclature List
V ............................................ Volt
WD ......................War Department
94
<9
TM 8-630
8
APPENDIX
Section III. LIST OF ALL SERVICE PARTS
8. INTERCHANGEABLE SERVICE PARTS.
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity
COMMON PARTS
SR00045 SCREW, 10-32 x % INCH, R.H.M.,
144 TO A PACKAGE: For magneto
ground wire. pkg.
14 SR00105 SCREW, 6-32 x % INCH, R.H.M.,
144 TO A PACKAGE: For fuel
pump valve. pkg.
*__ SR00141 SCREW, 10-32 x 5/16 INCH, R.H.M.,
144 TO A PACKAGE: For bell
housing band and cylinder air
housing. pkg.
*__ SR00145 SCREW, 10-32 x li/2 INCH, R.H.M.,
144 TO A PACKAGE: For spark
plug shields. pkg.
*11 SR00151 WASHER, LOCK, SCREW SIZE 10:
For spark plug shield and carburetor
cover. lb.
14 SROO152 WASHER, LOCK, SCREW SIZE 8:
For fuel pump flange. lb.
*__ SROO156 WASHER, LOCK, SCREW SIZE 5/16:
For fuel pump to adapter and fuel
tank. lb.
— SROO157 WASHER, SHAKEPROOF, SCREW
SIZE 10, EXT.: For jumper terminal.
pkg.
18 SR00215 NIPPLE, CLOSE, PIPE, 3/8 INCH:
For oil drain. ea. 1
*11, 12 SR00229 WASHER, LOCK, SCREW SIZE lb.
17 SROO23O NUT, % x 20, HEX, 144 TO A
PACKAGE: For governor and governor
arm ball joint. pkg-
— SR00273 NUT, 10 x 32, HEX, BRASS, 144
TO A PACKAGE: For generator
jumper terminal. pkg.
14 SR00280 SCREW, 8-32 x % INCH, FILL.
H.M.: For fuel pump flange. pkg-
— SR00293 WASHER, SCREW SIZE For
governor ball joint, governor shaft
and connecting rod. lb.
12 SR00297 WASHER, SCREW SIZE y4: For
throttle shaft. lb.
95
TM 8-630
8
X-RAY FIELD UNIT GENERATOR
Figure
No.
Medical
Dept. No.
Nomenclature Unit Quantity
11, 12 SR00314 SCREW, 10-32 x 5/8 INCH, R.H.M.,
144 TO A PACKAGE: For choke
arm. pkg-
*11, 12, 17 SROO33O NUT, 10 x 32, HEX, 144 TO A
PACKAGE: For governor arm adjusting
screw, spark plug shield and
throttle adjusting screw. Pkg-
— SROO337 WASHER, SCREW SIZE i/2: For
blower wheel. lb. -
*__ SROO358 WASHER, LOCK, SCREW SIZE l/2:
For blower wheel. lb.
*_ SR00404 WASHER, SCREW SIZE 5/16: For
generator brush. lb.
$_r— SR00422 NUT, 5/16 x 18, HEX, 144 TO A
PACKAGE: For fuel tank. pkg-
18 SROO451 COUPLING, PIPE, y8 INCH: For
oil drain. ea. 1
— SROO551 WASHER, SHAKEPROOF, SCREW
SIZE 14, INT: For governor. lb.
19 SR00664 NIPPLE, LONG, PIPE, l/8 INCH x
2/8 INCH: For oil pump inlet. ea. 1
*7 SR00665 NUT, 5 x 40, HEX, BRASS: For
locking stationary point. pkg-
— SR00666 NUT, JAM, y8 x 16, HEX: For oil
pump relief valve. pkg-
11, 12 SR00672 NUT, 10 x 32, SQUARE: For choke
arm. pkg-
*1 SROO685 NUT, 5/16 x 18, WING: For case. pkg-
*— SR00687 NUT, JAM, i/2 x 13, HEX: For
blower wheel. pkg-
*____ SR00688 SCREW, 1/4-20 x UA INCH, ALLEN
HEAD, CAP: For exhaust muffler. pkg-
*___ SR00719 SCREW, 1/4-20 x 2 INCH, ALLEN
HEAD, CAP: For intake manifold. pkg-
*__ SR00720 SCREW, 1A-20 x 5/16 INCH, ALLEN
H.M.: For blower housing. pkg-
*— SR00721 SCREW, 1/4-20 x 5/8 INCH, ALLEN
H.M.: For carrying assembly. pkg-
*17 SR00722 SCREW, 1/4-20 x y4 INCH, ALLEN
H.M.: For generator brush and governor
shaft. Pkg-
96
TM 8-630
8
APPENDIX
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity
12 SR00723 WASHER, LOCK, SCREW SIZE 5:
For choke plate. lb.
❖_ _ SR00724 SCREW, 5/16—18 x 1 INCH, ALLEN
H.M.: For fuel pump and generator
pole shoes. pkg.
— SROO725 SCREW, 8-32 x INCH, HEX
H.M.: For governor pivot plate. Pkg.
— SR00801 SCREW, 1/-20 x 5/8 INCH, HEX
HEAD, CAP: For carburetor. Pkg-
•— SR00802 SCREW, %-16 x % INCH, HEX
HEAD, CAP: For oil pump relief
valve. pkg-
*— SROO8O3 SCREW, 5/16-18 x % INCH, R.H.M.:
For fuel tank. pkg.
*__ SR00804 SCREW, 5/16-18 x 1% INCH, R.H.M.:
For fuel tank. pkg.
— SROO8O5 SCREW, 10-32 x l/2 INCH, R.H.M.,
BRASS: For generator jumper terminal.
pkg.
❖_ SR00806 STUD, 5/16-24 x 1% INCH: For
cylinder base. ea. 10
*— SR00807 STUD, 5/16-24 x 2i/8 INCH: For
cylinder heads. ea. 12
— SR00808 WASHER, SCREW SIZE 5/16, COPPER:
For fuel pump. lb.
*19 SR00809 SCREW, 1^-28 x 1 INCH, HEX
HEAD, CAP: For connecting rod. pkg.
*__ SR00810 STUD, 3/8-24 x 1% INCH: For oil
base. ea. 4
❖__ SR00811 SETSCREW, 1A-20 x % INCH,
ALLEN HEAD, CONE PT.: For
starter rope pulley. pkg.
*11, 12, 17 SR00813 SCREW, 10-32 x 1/2 INCH, FILL.
H.M.: For throttle stop and carburetor
cover. pkg.
11, 12, 17 SR00814 SCREW, 10-32 x % INCH, FILL.
H.M.: For throttle stop adjusting
screw. pkg-
11, 12, 17 SROO815 SCREW, 10-32 x 9/16 INCH, HEX
H.M.: For throttle arm. pkg.
*11, 12 SR00816 SCREW, 14-28 x 1% INCH, HEX
H.M.: For carburetor. pkg.
97
TM 8-630
8
X-RAY FIELD UNIT GENERATOR
Figure
No.
Medical
Dept. No.
Nomenclature Unit Quantity
12 SR00817 SCREW, 5-40 x 1A INCH, O.H.M.:
For throttle plate. pkg-
12 SR00818 SCREW, 5-40 x 3/16 INCH, R.H.M.:
For choke plate. pkg.
Tools
*2 TRO1O33 BRUSH, WIRE, 14 INCH HANDLE: ea. 1
*2 TRO 135 5 FILE, IGNITION POINT: ea. 1
*2, 9 TR01430 GAGE, FEELER, .001 INCH TO
.025 INCH: ea. 1
*2 TR01610 PLIER, SLIP JOINT, SHEAR CUTTING,
6 INCH: ea; 1
*2 TRO17O5 SCREWDRIVER, NORMAL DUTY,
i/4 INCH SHANK, 4 INCH
BLADE LENGTH: ea. 1
*2 TR01710 SCREWDRIVER, NORMAL DUTY,
1A INCH SHANK, 6 INCH
BLADE LENGTH: ea. 1
*2 TR01865 WRENCH, ADJUSTABLE, AUTO
TYPE, 8i/2 INCH LENGTH, 278
INCH OPENING: ea. 1
*2 TRO1915 WRENCH, SETSCREW, ALLEN,
NO. 10: ea. 1
*2 TR01918 WRENCH, SETSCREW, ALLEN, i/4
INCH: ea. 1
*2 TR01921 WRENCH, SETSCREW, ALLEN, 5/16
INCH: ea. 1
*2 TR01924 WRENCH, SETSCREW, ALLEN, %
INCH: ea. 1
*2 TR02045 WRENCH, DOUBLE END, ENGINEER,
15 DEGREE, /8 INCH x
7/16 INCH: ea. 2
*2 TR02048 WRENCH, DOUBLE END, ENGINEER,
15 DEGREE, 7/16 INCH x
i/2 INCH: ea. 2
*2 TR02054 WRENCH, DOUBLE END, ENGINEER,
15 DEGREE, 9/16 INCH x
5/8 INCH: ea. 2
*2 TRO2O57 WRENCH, DOUBLE END, THIN
HEAD, 15 DEGREE, 5/8 INCH x
11/16 INCH: ea. 1
*2, 7 TR02080 WRENCH, IGNITION POINT, FOR
NUT SCREW—SIZE 5: / ea. 1
98
TM 8-630
8-9
APPENDIX
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity
*2 TR02215 WRENCH, SPARK PLUG, 27/32
INCH x 1-1/32 INCHES: ea. 1
*2 TRO2255 ADAPTER, SOCKET WRENCH, l/2
INCH FEMALE SQUARE DRIVE,
9/16 INCH ROUND HANDLE
HOLE: ea. 1
*__ TRO231O HANDLE, SPARK PLUG WRENCH,
SOLID, s/8 INCH DIA., 6 INCH
LENGTH: ea. 1
*2 TRO2315 HANDLE, SOCKET WRENCH, BAR
TYPE, 9/16 INCH DIA, 10 INCH
LENGTH: ea. 1
*2 TRO2355 PLUG-CONNECTOR, SOCKET
WRENCH, i/2 INCH SQUARE
DRIVE, iy4 INCH LENGTH: ea. 1
*2 TR02425 SOCKET, 7/16 INCH 12 POINT
OPENING, 1/2 INCH SQUARE
DRIVE: ea. 1
*2 TR02428 SOCKET, 1/2 INCH 12 POINT
OPENING, 1/2 INCH SQUARE
DRIVE: ea. 1
*2 TR02431 SOCKET, 9/16 INCH 1.2 POINT
OPENING, 1/2 INCH SQUARE
DRIVE: ea. 1
9. SERVICE PARTS FOR MODEL OTC-38 ONLY.
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity
*9, 18 9R00602
UNCOMMON PARTS
Cylinder group
CYLINDER, C.L, 2% INCH, R/H.: ea. 1
*9, 18 9R00604 CYLINDER, C.L, 2% INCH, L/H.: ea. 1
*9, 18 9R00606 GASKET, CYLINDER BASE: ea. 2
*9, 18 9R00608 HEAD, CYLINDER, R/H.: ea. 1
*9, 18 9R00610 HEAD, CYLINDER, L/H.: ea. 1
*3, 9, 18 9R00612 GASKET, CYLINDER HEAD: ea. 2
*9, 19 9R00614
Valve group
VALVE, INTAKE: ea. 2
*9, 19 9R00616 VALVE, EXHAUST: ea. 2
99
TM 8-630
9
X-RAY FIELD UNIT GENERATOR
Figure
No.
Medical
Dept. No.
Nomenclature Unit Quantity
*9, 19 9R00618 GUIDE, VALVE: ea. 4
*9, 19 9R00620 SPRINGS, VALVE: ea. 4 .
9 9R00621 NUT, LOCKING, TAPPET: ea. 4
*9 9R00622 TAPPET, VALVE: ea. 4
*9, 19 9R00623 LIFTER, VALVE: ea. 4
*9, 19 9R00624 PIN, VALVE: ea. 4
19 9R00625 INSERT, VALVE SEAT: ea. 4
*9, 19 9R00626 WASHER, VALVE: ea. 4
9, 18 9R00627 COVER, VALVE: ea. 2
*3, 9, 18 9R00628 GASKET, VALVE COVER: ea. 2
19 9R00629
Piston and connecting rod group
PIN, PISTON: ea. 2
*9, 19 9R00630 PISTON, 2/4 INCH BORE: ea. 2
*9, 19 9R00632 RINGS, PISTON, SET: 2 Compression
and 1 oil. set 2
*19 ’9R00637 WASHER, CONNECTING ROD
SCREW: ea. 2
*9, 19 9R00638 RING, LOCK, PISTON PIN: ea. 4
19 9R00639 BUSHING, PISTON PIN: ea. 4
*19 9R00640 ROD, CONNECTING, COMPLETE:
Assembly. ea. 2
*19 9R00641 INSERT, ROD, CONNECTING
BEARING: ea. 4
*__ 9R00644
Manifold group
MUFFLER, EXHAUST: ea. 1
*_ _ 9R00646 MANIFOLD, INTAKE: ea. 1
*3 9R00648 GASKET, MANIFOLD: ea. 4
*__ 9ROO65O ADAPTER, MANIFOLD: ea. 2
*_ 9R00652 TUBE, MANIFOLD: ea. 2
*19 9R00656
Camshaft group
BEARING, CAMSHAFT, FRONT: ea. 1
*19 9R00658 BEARING, CAMSHAFT, REAR: ea. 1
19 9R00659' WASHER, SPACER, CAMSHAFT
GEAR: ea. 1
*7, 19 9R00660 GEAR, CAMSHAFT: ea. 1
100
TM 8-630
9
APPENDIX
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity
Governor group
16 9R00661 SCREW, CUP STOP, GOVERNOR: ea. 1
*7, 16 9R00662 WEIGHT, GOVERNOR: ea. 4
16 9R00663 SPACER, CUP STOP SCREW,
GOVERNOR: ea. 1
❖_ 9R00664 BEARING, CUP, GOVERNOR: ea. 1
16 9R00665 PLATE, PIVOT, GOVERNOR: ea. 1
7, 16 9R00667 CUP AND STUD, GOVERNOR: ea. 1
*7, 16, 17 9R00668 ROD, ARM, GOVERNOR: ea. 1
16 9R00669 STUD, GOVERNOR: ea. 1
*7, 16, 17 9R00670 JOINT, BALL, GOVERNOR: ea. 1
*16 9R00672 PIN, WEIGHT, GOVERNOR: ea. 4
Crankshaft group
\*19 9R00674 CRANKSHAFT: ea. 1
*19 9R00676 SEAL, OIL, CRANKSHAFT: ea. 1
*19 9R00678 BEARING, CRANKSHAFT: pr. 1
*19 9R00680 GEAR, CRANKSHAFT: ea. 1
*19 9R00682 NUT, CRANKSHAFT: ea. 1
Gearcase, crankcase, oil base group
18 9R00701 BEARING PLATE AND GENERATOR
SUPPORT: ea. 1
*18 9R00702 GASKET, BEARING PLATE AND
GENERATOR SUPPORT: ea. 1
— 9R00703 GASKET, OIL FILLER CAP: ea. 1
*18 9R00704 BASE, OIL: ea. 1
*18 9ROO7O5 GASKET, OIL BASE: ea. 1
*18 9R00706 PLUG, OIL: ea. 1
7 9R00707 CAP AND BUSHING, OIL FILLER: ea. 1
5, 7 9R00709 GAGE AND CHAIN, OIL FILLER: ea. 1
*— 9R00712 SEAL, OIL, GEARCASE: ea. 1
Carburetor and air cleaner group o'ne
12 9R00713 PLUG, METERING WELL, CARBURETOR:
ea. 1
*__ 9R00714 CARBURETOR, ZENITH TU3, Yl: ea. 1
101
TM 8-630
9
X-RAY FIELD UNIT GENERATOR
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity
8 9R00715 ELBOW, CARBURETOR: ea. 2
*12 9R00716 JET, MAIN, CARBURETOR: ea. 1
—- 9R00717 CLIP, MANUAL CHOKE: ea. 1
5 9R00719 CONTROL, MANUAL CHOKE: ea. 1
*12 9R00720 VALVE AND SEAT, CARBURETOR: ea. 1
*12 9R00721 WASHER, LOWER, METERING
WELL, CARBURETOR: ea. 1
*12 9R00722 WELL, METERING, CARBURETOR: ea. 1
11, 12 9R00723 PLUG, DRAIN AND COVER, CARBURETOR:
ea. 2
*11 9R00724 GASKET, CARBURETOR TO MANIFOLD:
ea. 1
*12 9R00725 WASHER, UPPER, METERING
WELL, CARBURETOR: ea. 1
11, 12 9R00727 BOWL, CARBURETOR: ea. 1
*12 9R00728 FLOAT, COMPLETE: ea. 1
*12 9R00729 WASHER, MAIN JET, CARBURETOR:
ea. 1
*11, 12 9R00730 GASKETS, CARBURETOR, SET:
Body to bowl and bowl to cover. set 1
12 9R00731 PIN, FLOAT, CARBURETOR: ea. 1
*7 9R00733 ADAPTER, AIR CLEANER: ea. 1
*4, 7 9R00734 CLEANER, AIR: ea. 1
*4, 7 9R00736 SCREEN, BREATHER TUBE: ea. 1
*7 9R00737 SCREW, LOCKING, AIR CLEANER
ADAPTER: ea. 1
*4 9R00738 GASKET, AIR CLEANER: ea. 1
Fuel supply group
14 9R00739 SPRING, LEVER, FUEL PUMP: ea. 1
*__ 9R00740 PUMP, FUEL, COMPLETE: Assembly
1537966. ea. 1
— 9R00741 PLATE, VALVE, FUEL PUMP: ea. 1
*_ 9R00742 FILTER, COMPLETE: Assembly. ea. 1
8, 14 9R00743 BODY, UPPER, FUEL PUMP: ea. 1
*3, 8 9R00744 LINE, FUEL, CARBURETOR: ea. 1
102
TM 8-630
9
APPENDIX
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity
13, 14 9R00745 VALVE, FUEL PUMP: For pressure
and vacuum. ea. 2
*3, 5 9R00746 LINE, FUEL, TANK: ea. 1
14 9R00747 CAP, BOWL, FUEL PUMP: ea. 1
*8, 13, 14 9R00748 GASKET, FUEL PUMP: ea. 1
8 9R00749 ROD, PUSH, FUEL PUMP: ea. 1
*4, 8 9R00750 GASKET, FUEL PUMP ADAPTER
AND BREATHER TUBE: ea. 2
8 9R00751 ADAPTER, FUEL PUMP: ea. 1
*4, 8, 14 9R00752 SCREEN, FUEL PUMP: ea. 1
8,14 9ROO753 NUT, BOWL YOKE, FUEL PUMP: ea. 1
*4, 5, 8, 14 9R00754 BOWL, FUEL PUMP: ea. 1
— 9ROO755 KEY, COTTER, FUEL PUMP PUSH
ROD: ea. . 1
*3,8,13,14 9R00756 GASKET, FUEL PUMP, BOWL: ea. 1
8, 14 9R00757 YOKE, BOWL, FUEL PUMP: ea. 1
_ 9R00758 KIT, FUEL PUMP: ea. 1
Ignition breaker group
— 9ROO759 NIPPLE, SPARK PLUG SHIELDING:
ea. 2
*7 9R00760 PLATE, BACK, MAGNETO: ea. 1
7 9R00761 SHOE, MAGNETO COIL, LAMINATED:
ea. 1
*7 9R00762 COIL, MAGNETO, RIGHT: ea. 1
5 9R00763 BUTTON, STOP: ea. 2
*7 9R00764 COIL, MAGNETO, LEFT: ea. 1
— 4 9R00765 NAMEPLATE, STOP BUTTON: ea. 2
*3, 7 9R00766 CONDENSER, MAGNETO: ea. 1
— 9R00767 NUT, COUPLING, SPARK PLUG
SHIELD: ea. 2
❖_ 9R00768 CABLE, S.P, MAGNETO, L/H.: ea. 1
— 9R00769 NUT, LOCK, SPARK PLUG
SHIELD: ea. 2
*— 9R00770 CABLE, S.P, MAGNETO, R/H.: ea. 1
103
TM 8-630
9
X-RAY FIELD UNIT GENERATOR
Figure
No.
Medical
Dept. No.
Nomenclature Unit Quantity
*7 9R00771 WIRE, MAGNETO TO CONDENSER:
ea. 1
*3 9R00772 ARM AND POINT, BREAKER: ea. 1
9R00773 WHEEL, BLOWER: ea. 1
*7 9R00774 PLUNGER, BREAKER: ea. 1
9R00775 SHIELD, SPARK PLUG, ASSEMBLY : ea. 2
*4, 7 9R00776 SPRING, BREAKER: ea. 1
— 9R00777 BRACKET, BREAKER SPRING: ea. 1
7 9R00779 BOX, IGNITION BREAKER: ea. 1
* j 9R00780 PLUG, SPARK: ea. 2
— 9R00781 COVER, BOX, IGNITION
BREAKER: ea. 1
*7 9R00782 STUD, ARM, IGNITION BREAKER: ea. 1
— ■ 9R00783 MOUNTING, CONTACT POINT,
ASSEMBLY: ea. 1
Generator group
*10 9R00784 ARMATURE, COMPLETE: ea. 1
10 9R00785 STUD, ARMATURE: ea. 1
*10 9R00786 RIG, BRUSH, COMPLETE: Assembly.
ea. 1
10 9R00787 STUD, GENERATOR FRAME: ea. 4
*3, 10 9R00788 BRUSH, DC: ea. 4
10 9R00789 BLOWER, GENERATOR: ea. 1
*10 9R00790 BEARING, BALL: ea. 1
*10 9R00791 NUT, STUD, GENERATOR FRAME: ea. 4
*10 9R00792 COIL SET, FIELD: ea. 1
10 9R00793 WASHER, STUD, ARMATURE: ea. 1
*3, 10 9R00794 SPRING, DC: ea. 4
10 9R00795 FRAME, GENERATOR: ea. 1
*10 9R00796 NUT, STUD, ARMATURE: ea. 1
10 9R00797 WIRE, AC BRUSH: ea. 2
*3, 10 9R00798 BRUSH, AC: ea. 4
'10 9R00799 COVER, BEARING, GENERATOR: ea. 1
104
TM 8-630
9
APPENDIX
Figure
No.
.Medical
Dept. No. Nomenclature Unit Quantity
*3, 10 9R00800 SPRING, BRUSH, AC: ea. 4
10 9R00801 BAND, END BELL HOUSING,
GENERATOR: ea. 1
* 10 9R00802 CONDENSER, LINE, AC 1—MFD: ea. 1
10 9R00803 HOUSING, END BELL, GENERATOR:
ea. 1
*3, 10 9R00804 GASKET, BEARING COVER: ea. 1
Governor-booster group
*16 9R00806 CONDUIT, FLEXIBLE, GOVERNOR-
BOOSTER: ea. 1
*— 9R00808 COIL AND HOUSING, GOVERNOR-
BOOSTER: ea. 1
Accessories
* 1, 5 9R00810 ROD, GROUNDING: ea. 1
*1, 4, 5 9R00812 CABLE, GROUNDING: ea. 1
*1, 5 9R00814 CABLE, NO. 12, TYPE S, 3 CONDUCTOR:
ft. 50
*1, 5 9R00816 CONNECTOR, ANGLE-CORD: ea. 1
*1, 5 9R00818 PLUG, ANGLE-CORD: ea. 1
*1, 4, 5 9R00820 CLIP, SPRING: ea. 2
*4, 10 9R00822 RECEPTACLE, DUPLEX: ea. 1
*3 9R00826 ROPE, STARTER: ea. 1
*3 9R00830 GASKET, FILLER CAP: For fuel
tank. ea. 1
*3 9R00832 GASKET, SHUT-OFF SCREW: For
fuel tank. ea. 1
5, 10 9R00838 PULLEY, STARTER ROPE: ea. 1
10 9R00840 SHOE, POLE: ea. 1
Governor-booster group section two
7, 16, 17 9R00842 NUT, ADJUSTING, GOVERNOR
SPRING: ea. I
7, 16, 17 9R00844 BRACKET, ADJUSTING SPRING,
GOVERNOR: ea. 1
16 9R00846 SPACER, SHAFT, GOVERNOR: ea. 1
105
TM 8-630
9
X-RAY FIELD UNIT GENERATOR
Figure
No.
Medical
Dept. No.
Nomenclature Unit Quantity
16 9R00848 BEARING, LOWER, SHAFT, GOVERNOR:
ea. 1
16 9R00850 BEARING, UPPER, SHAFT, GOVERNOR
: ea. 1
7, 16, 17 9R00852 STUD, SPRING, GOVERNOR: ea. 1
16 9R00854 BRACKET, BOOSTER: ea. 1
7, 16 9R00856 HOUSING, BOOSTER: ea. 1
7, 16 9R00858 COVER, HOUSING, BOOSTER: ea. 1
16, 17 9R00860 PLUNGER, BOOSTER: ea. 1
16, 17 9R00862 SCREW, ADJUSTING, GOVERNOR
SPRING: ea. 1
7, 16, 17 9R00864 ROD, CONTROL, THROTTLE: ea. 1
7, 16, 18 9R00866 SHAFT AND PADDLE, GOVERNOR:
ea. 1
16 9R00868 COIL, BOOSTER: ea. 1
5, 10 9R00869 OUTLET, CONDUCTOR CABLE: ea. 1
Air housing group
— 9R00870 HOUSING, BLOWER: ea. 1
— 9R00872 HOUSING, AIR, R/H. CYLINDER: ea. 1
— 9R00874 HOUSING, AIR, L/H. CYLINDER: ea. 1
— 9R00876 GROMMET, RUBBER, CYLINDER
AIR HOUSING: ea. 2
Fuel tank group
— 9R00878 TANK, FUEL: ea. 1
5 9R00880 CAP AND CHAIN, FILLER, FUEL
TANK: ea. 1
— 9R00882 SCREW, SHUT-OFF, FILLER CAP: ea. 1
— 9R00884 SPRING, SHUT-OFF SCREW,
FILLER CAP: ea. 1
5 9R00886 PETCOCK, SHUT-OFF, FUEL
TANK: ea. 1
Carrying case group
— 9R00888 FRAME, CARRYING: ea. 1
1 9R00890 HANDLE, CARRYING: ea. 2
106
TM 8-630
9
APPENDIX
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity-
1, 5 9R00892 PANEL, LEFT SIDE: ea. 1
1, 5 9R00894 PANEL, RIGHT SIDE: ea. 1
1 9R00896 BOX, TOOL AND SPARE PART: ea. 1
1 9R00898 BRACKET, CLAMP: ea. 2
1 9R00900 CLASP, TRUNK: ea. 14
1 9R00902 SNAP AND CHAIN, HARNESS: ea. 14
1 9ROO9O4 COVER, WIRE COMPARTMENT: ea. 1
1, 5 9R00906 PANEL, TOP, CABLE COMPARTMENT:
ea. 1
1, 5 9R00908 PANEL, BACK: ea. 1
1 9R00910 PANEL, FRONT: ea. 1
1, 5 9ROO912 PANEL, BASE AND SKID: ea. 1
7 9R00914 WIRE, CONDENSER TO POINTS: ea. 1
1 9R00916 HANDLE, COVER, WIRE COMPARTMENT:
ea. 1
1 9R00918 HANDLE, BOX, TOOL AND SPARE
PART: ea. 2
Carburetor group two
11, 12 9R00920 WASHER, DRAIN AND COVER
PLUG, CARBURETOR: ea. 1
11, 12 9R00922 COVER, CARBURETOR: ea. 1
11, 12 9R00924 NAIL, METAL, SERIAL PLATE,
CARBURETOR: ea. 1
11, 12 9R00926 PLATE, SERIAL, CARBURETOR: ea. 1
12 9R00928 PLATE, CHOKE, CARBURETOR: ea. 1
11, 12 9R00930 SHAFT, CHOKE, CARBURETOR: ea. 1
11, 12 9ROO932 ARM, CHOKE, C*ARBURETOR: ea. 1
11, 12 9R00934 NEEDLE, IDLE JET, CARBURETOR: ea. 1
11, 12 9R00936 SPRING, IDLE JET, CARBURETOR: ea. 1
11, 12 9R00938 BODY, CARBURETOR: ea. 1
11, 12, 17 9R00940 ARM, THROTTLE, CARBURETOR: ea. 1
11, 12, 17 9R00942 STOP, THROTTLE ARM, CARBURETOR
: ea. 1
107
TM 8-630
9
X-RAY FIELD UNIT GENERATOR
Figure
No.
Medical
Dept. No.
Nomenclature Unit Quantity
11, 12, 17 9R00944 SHAFT, THROTTLE, CARBURETOR:
ea. 1
12 9R00946 PLATE, THROTTLE, CARBURETOR:
ea. 1
Fuel supply group two
13, 14 9R00948 DIAPHRAGM AND LEVER LINK,
FUEL PUMP: ea. 1
14 9R00950 SPRING, DIAPHRAGM, FUEL
PUMP: ea. 1
8, 14 9R00952 BODY, LOWER, FUEL PUMP: ea. 1
14 9R00954 LEVER, FUEL PUMP: ea. 1
13, 14 9R00956 GASKET, VALVE, FUEL PUMP: ea.' 2
UNCOMMON PARTS
—• 9R00726 ADJUSTER, MAIN JET: ea. 1
*7 9R00805 SPRING, GOVERNOR-BOOSTER: ea. 1
*20 9R00958 CAMSHAFT: ea. 1
*18 9R00960 CRANKCASE, WITH BEARING
PLATE ASSEMBLY: Assembly. ea. 1
— 9R00962 GEARCASE, ALUMINUM: ea. 1
❖_ 9R00964 GASKET, GEARCASE: ea. 1
— 9R00966 BOLT, MAGNETO: ea. 1
—• 9R00968 PLUG, CLEANING, OIL PUMP: ea. 1
—■ 9R00969 BALL, CHECK, INLET, OIL PUMP: ea. 1
— 9R00970 SEAT, RELIEF VALVE, OIL PUMP: ea. 1
— 9R00971 BALL, CHECK, OUTLET, OIL
PUMP: ea. 1
*20 9R00972 SCREEN, OIL PUMP: ea. 1
*20 9R00974 LINE, OIL, FRONT BEARING: ea. 1
*20 9R00976 LINE, OIL, REAR BEARING: ea. 1
20 9R00977 BODY, OIL PUMP: ea. 1
*__ 9R00978 PUMP, OIL, COMPLETE: ea. 1
20 9R00980 PLUNGER, OIL PUMP: ea. 1
108
TM 8-630
9-10
APPENDIX
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity
20 9R00982 SPRING, PLUNGER, OIL PUMP: ea. 1
20 9R00984 ARM, CAM FOLLOWER, OIL
PUMP: ea. 1
20 9R00986 SHAFT, CAM FOLLOWER ARM,
OIL PUMP: ea. 1
20 9R00988 ROD, PUSH, OIL PUMP: ea. 1
— 9R00990 BALL, RELIEF VALVE, OIL PUMP: ea. 1
*20 9R00992 VALVE, RELIEF, OIL PUMP, COMPLETE:
Assembly. ea. 1
— 9R00994 SPRING, RELIEF VALVE, OIL
PUMP: ea. 1-
— 9R00996 TEE, PIPE, OIL PUMP: ea. 1
— 9R00998 BODY, RELIEF VALVE, OIL PUMP: ea. 1
— 9R01000 CRANKCASE: ea. 1
10. SERVICE PARTS FOR MODEL OTC-38B ONLY.
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity
UNCOMMON PARTS
*7, 19 9R00654 CAMSHAFT: ea. 1
*16, 17 9R00666 SPRING, GOVERNOR: ea. 1
19 9R00683 RING, SCREEN LOCK, OIL PUMP: ea. 1
19 9R00685 BODY AND IDLER SHAFT, OIL
PUMP: ea. 1
*__ 9R00686 SPRING, RELIEF VALVE, OIL
PUMP: ea. 1
*19 9R00687 VALVE, RELIEF, OIL PUMP: ea. 1
18 9R00689 COVER, OIL PUMP: ea. 1
19 9R00691 GEAR AND SHAFT, BODY
DRIVER, OIL PUMP: ea. 1
19 9R00693 GEAR, DRIVE, OIL PUMP: ea. 1
*_ 9R00694 PUMP, OIL, COMPLETE: Assembly. ea. 1
19 9ROO695 GEAR, IDLER, OIL PUMP: ea. 1
109
TM 8-630
10
X-RAY FIELD UNIT GENERATOR
* To be requisitioned, when required, from the supply depot.
Figure
No.
Medical
Dept. No. Nomenclature Unit Quantity
*19 9R00696 SCREEN, OIL PUMP: ea. 1
19 9R00697 CUP, INTAKE, OIL PUMP: ea. 1
*18 9R00698 GASKET, OIL PUMP: ea. 1
*9, 18 9R00700 CRANKCASE, WITH BEARING
PLATE ASSEMBLY: Assembly. ea. 1
*9, 18 9R00708 GEARCASE: ea. 1
*18 9R00710 GASKET, GEARCASE: ea. 1
18 9R00711 CRANKCASE: ea. 1
— 9R00834 PIN, GEAR, OIL PUMP: ea. 1
— 9R00836 CUP, DEFLECTOR, RELIEF VALVE
OIL PUMP: ea. 1
19 9R00837 NUT, DRIVE GEAR, OIL PUMP: ea. 1
No asterisk indicates that the item is not stocked as a Spare Part, but can be obtained by
special requisition.
110
TM 8-630
INDEX
Paragraph Page
Abbreviations, list of ................................................................................ App. 93
AC winding, testing ...... . ...................................... 101c 91
Accessories ..........................................................;............ 7 8
Adapter, air cleaner:
Installing ............................................................................ 49a, 94h 35, 87
Removing .................................................... ;................. 49a, 79a 35, 71
Adjust, definition of ...... .................................... ............................................33b 19
1 / Adjusting screw, governor—booster spring ..................................................Ilf 11
Adjustment:
Carburetor ................... ..................................................... 62 a 52
Governor-booster .................................................................................77a, b 69, 70
Fuel pump ................................................................................................67a 57
Magneto ............................ f..........................................................72a 60
Valve tappet .......................... :............. 52c 37
After operation services .................................................................................. 32 17
Air cleaner adapter:
Installing ............... .-......... 49a, 94h 35, 87
Removing .........................................................................................49a, 79a 35, 71
Air cleaner:
Cleaning ...........1............. .....................................................................48 35
Clogged ....................................................................... 35a 23
Function .............................................................................................. 47a, b 35
Removing and installing .........................................................................48a 35
Air housing, blower:
Installing ................ .:............ .............. 93p 86
Removing ....................... 80c 73
Air housings, cylinder:
Installing ................................................................................ 52d, 95c 37, 88
Removing ........................................................................................_52a, 80c 36, 73
Air lock .......................................................................................................... 35b 23
All parts list (SNL) reference .......................... App. , 93
All service parts list -.................................. App. 93
Arm, cam follower, oil pump OTC-38, inspecting ...................................81c 79
Armature, testing ...........—...... _.101b, c 91
Army Regulations, references .............. App. 93
ASF Medical Supply Catalog, references ....................... App. 93
Assembling new or used equipment .............................................................9b 9
Auxiliary equipment ...... 18,56 12,46
Ball bearing, generator, lubricating ............ 55i 44
Ball check seats, oil pump OTC-38, inspecting ........... 81c 79
Bars, commutator ......................................................................................100a 89
Base, oil:
Cleaning .... .................................................. 86a 81
Inspecting .................................................. ............................................... 86b 81
Installing on crankcase .............................................. 93k 85
Removing ...................................................................................... .....:....80j 76
Bearing:
Camshaft:
Clearance ...... . ................. ,......................................... 80h 76
Inspecting ....................................................................................... 85b 81
Connecting rod:
Clearance .................................... ■...........78c 71
Inspecting ................................. _...............88b 82
Crankshaft:
Clearance .. ..... ......................... 78c 71
Inspecting ..................................................................................... ..8 5b 81
III
TM 8-630
X-RAY FIELD UNIT GENERATOR
Plate and generator support: Paragraph
Cleaning ................................. _.......................... 85a
Inspecting .......... '..........85b
Installing .................................................................
Removing ........................................................... 80n
Before operation service ............................................................ 29
Blower housing:
Installing ..................................................... ............... ........................
Removing .......... ....................................................... ~Z.80c
Booster:
Disassembling ....... 74d
Function .........._....................................................................
Installing ........... ........................................................ -jM
Reassembling ............ _.
Removing ........................................................................... y4c
Booster coil:
Installing .......................................................................
Removing .................................................................... 79c]
„ Testing ...................................................................................’... 7.70b
Booster-governor:
Adjusting ....„„.„x........... ............................ 77a> b
Testing ........................................................................ .......................,.....77b
Spring adjusting screw ....................:........................
Booster parts:
Cleaning ............................................. 1.:...i......................_ 75e
Inspecting .................................................................................... 75f
Lubricating .................................................................... 75b
Replacing .................................................................... 7.7.75g
Bowl, fuel pump, cleaning and replacing ........................ 45a
Breaker. (See Ignition breaker.)
Breaker—
Page
81
81
83
77
16
86
73
66
61
68
68
66
87
72
58
69, 70
70
11
67
67
67
67
34
Arm and points ....-......... ............................. ....38a
Box:
Installing ...:..................................... . ... 94b
Removing ................................ ... 79g
Points:
Inspecting.......................
Refacing .................................................... ... 38e
Replacing ................................................. ....38f
Setting gap................................................. .. .3811
Breaker and magneto, testing ....................... .....40
Breather tube:
Installing .................................. ...... . ...... ...94d
Removing .............................................. ... 79e
Breather tube screen, cleaning and replacing ..... ... 49a
Brush holders, cleaning ............................ ...98d
Brush rig:
Installing ............................................ ...103a
Off neutral ....................................... - ..
Removing ........... ........ 97d
Brush springs:
Broken ..... ............. 36b
Inspecting .................................................. ... 55c
Replacing ................... ... ...55h
Resting on holders .............................. ... 36b
Brushes:
Binding in holders .......................
Cleaning ............... 98d
Inspecting ............... 55b
Noisv ................................
Replacing .............................. ss7
Worn .................. ...................... .. Button, stop ............. ^6b 1 le
Cable:
Conductor:
Broken .............................................. ...36b
Short circuit .................... ..............................................................35b
27
87
72
27
27
27
30
30
87
72
35
89
91
26
89
26
41
44
26
26
89
41
26
44
26
11
26
23
112
TM 8-630
INDEX
Outlet: Paragraph
Installing .................. 103d
Removing ..............................;................................................. 97b
Spark plug, cleaning and inspecting ......................................................39
Cam follower arm, inspecting ........................................................... 81c
Camshaft:
Cleaning ......................................................_........................................... 90a
Inspecting ....................................................................................... 90b
Installing ............... 93a
Removing ........................................................................................... ...80p
Camshaft bearing:
Clearance ......................................................................... 78C
Inspecting ....................................................................ZZZZ ZZ 85b
Camshaft journal, inspecting ................... 85b
Cap, fuel tank ...... .............................................................................. 11C
Capacitor (condenser) .................................................................................. 35g
Capacities, fuel and oil ........................ 4C
Carbon, removing ..._................................... 52b
Carburetor:
Adjusting ....................................... 62a
Cleaning ................................. 60a
Disassembling ..................................... 59b
Function ............................................... ’......................... 47a b
Inspecting .......................................................................ZZ...ZZZ... 60b
Installing ..................................... gib, 94c
Parts, replacing ......:............................ 60a
Reassembling ............................................. g[a
Removing .................................................................................. "59^ 79f
Testing ........................ 62b
Carburetor fuel line, cleaning and replacing ........................................ ...45b
Carburetor idle jet needle ....................................................... ng
Choke .................................................. ...........................
Choking ......................... 29b
Clean, definition of .................................................................................. 33b
Cleaning carbon ..............................................................................................52b
Clearances, engine ....................................... 78C
Coil:
Booster:
Installing ................ 94e
Removing .............................................. :........................................ 79J
Testing ...............,...................... ZZZZZZZjOb
Field:
Replacing .................................................................... v........ ........ 103b
Testing .......................................................................................10Id, e
Magneto:
Installing ....................................... ...........«■...............................71 a
Removing ............................................................. 69b
Testing .................................................................1Z..ZZ. 70b, 72b
Cold, operation in extreme ......................... 20
Collector rings. (See Slip rings.)
Common parts list, reference ............................. _..........„App.
Commutator:
Cleaning ..—........... 98b
Inspection ....... —..................... 55^ 100a
Sanding ................................. _..................... ......... _... ......... 98c
Undercutting ........ _......... ............................... 102
Compression, testing .......................................................... 53
Condenser, magneto:
Replacing ............... 35& 41b
Testing _.......................................... ................................. '................. 41a
Conductor cable;
Broken .............................. ......... ............ .......... ...... .........._ 36b
Short circuit ................................................. _ 35b
Conductor cable outlet:
Installing ----- -- --------—...... __................ _...... 10 3d
Removing ...................... _............. ........ ......... ......................_................ 97b
Page
92
88
30
79
82
82
83
77
71
81
81
11
25
8
36
52
49
47
35
49
49, 87
49
49
47, 72
5'2
34
11
11
16
19
36
71
87
72
58
91
91
58
57
58, 60
13
93
89
41, 89
89
91
40
25, 30
30
26
23
92
88
113
TM 8-630
X-RAY FIELD UNIT GENERATOR
Connecting rods: Paragraph
Cleaning .............................................................................................. 88a
Inspecting ................................................................................................88b
Installing on crankshaft .............................................. ......... . 93]
Installing in piston .................................................................................. 931
Connecting rod bearing clearance ........ .................................... .......... 78c
Connecting X-ray machine .............................................................................16
Control, choke ...............................................................................................
Correctly assembled, definition of ........................................ 27d
Crankcase:
Cleaning ................................................................................................... 85a
Inspecting ................................................................................................85b
Crankshaft:
Cleaning ................................................................................................... 89a
Inspecting...................... 89b
Installing 9.3a
Removing ..................... 80p
Crankshaft bearing:
Clearance ...................... ..................... ............................ y8c
Inspecting ....................... ,.......................................................................85b
Crankshaft gear:
Installing ............................................................. 93f
Removing ................................................................................................80i
Crankshaft journal, inspecting ... ..............................................85b, 89b
Crankshaft oil seal:
Installing ................................................................................................. 93b
Removing ....... 80o
Cutting down commutator ... 102
Cylinder air housings:
Installing ........................................................................................ 52d, 95c
Removing ........................................................................................ 52a, 80c
Cylinder heads:
Cleaning .......................................................................... 83a
Inspecting ........................ 83b
Installing ........................•...................................... .................... 52d, 93o
Removing ....................................................................................... 52a, 80d
Cylinders:
Cleaning ........................................................................................... 84a
Inspecting .............................................................................. 84b
Installing ............................................................................................ 93b
Removing ................................................................................ZZZZZ 80d
Data .................................................................................................. 4
DC winding, testing ........................ , jQib
Definitions:
Adjust .............................................................................................. 33b
Clean .........................................................................................................33b
Correctly assembled ............................................................................27d e
Excessively worn ............................................ 27f
Generator ....................................................................................... 54b’ 96c
Good condition ........... ................... .............................. _ 27c
Service.................................................................................. 33b
Tightening ................................................................................................33b
Demolition ............... 23
Disconnecting X-ray machine .. 17a
Dismounting:
Engine 80a
Generator .................................................................................................80b
Domestic shipment, preparation for App.
During operation services ..................................................... 30
Engine:
Adjusting .................................................................................................95b
Disassembling ............. 8q
Reassembling .......... .............................................................-•... ...... 93
Removing .......................................... _..................................................... 80a
Starting ........................................................................._.............................14
Stopping ......................................................... _...................... '..._/17
Trouble shooting ....................................... 35
Page
82
82
85
84
71
12
11
15
81
81
82
82
83
77
71
81
84
76
81, 82
83
77
91
37, 88
36, 73
80
80
37, 85
36, 73
80
81
84
73
8
91
19
19
15
15
40, 88
15
19
19
13
12
72
73
93
16
88
72
83
72
11
12
23
I 14
TM 8-630
INDEX
Paragraph Page
Engine date ....................................................................................................... 4a 8
Engine fuel:
Capacities .......................................—........... 4c 8
Specifications ................................................... 29b 16
Engine oil:
Capacities ..... i......................................... 4c 8
Specifications ......................... 26 15
Engine overheating ........_......... 35c 24
Engine performance .................... 4b 8
Engine warm-up ........ 15, 29b 12, 16
Excessive carbon ......................................................................... 35c 24
Excessively worn, definition of . 27f 15
Exhaust:
Muffler:
Installing ................. 94g 87
Removing ....... 1,................ . .........................i.........:...................79b 71
Vent .. ...................................... ................................. 9d 9
Failure to start ................. 35a 27
Field coils:
Installing .................................... 103b 91
Testing ............................................ lOld, e 91
Field Manuals, references ...................... ........................................App. 103
Filler cap shut-off:
Screw ...................................... 11c 11
Vent .......... _..... 44b 32
Filler gauge, oil ... ............................... 12 11
Follower, cam, inspecting ...................... 81c 79
Forms, list of ............ App. 103
Fuel, engine:
Capacity ........ .......... .... ................. ................................ :.........4c 8
Specification ............................................................................................. 29b 16
Fuel lines:
Cleaning ....... 44d, 45b 34
Flushing ........................................ ."...........44e 34
Replacing ....... 44d, 45b 34
Fuel pump:
Adjusting .......... 67a 57
Cleaning ... ....................... 65a 55
Disassembling ........... 64b 55
Models ................................. 63a 52
Inspecting .............................. 65b 55
Installing ...........................:....................... 66b, 94f 56,87
Reassembling .................................................. ,.......................66a 56
Removing ................ 1....................... 64a, 79c 55,71
Testing ...................................................................................... _....... 67b 57
Fuel pump bowl, cleaning and replacing .................................... 45a 34
Fuel pump kit ..............._.................... ........................................................... 63b 52
Fuel pump parts, replacing ................................ 65c 56
Fuel pump screen, cleaning and replacing .................... 45a 34
Fuel supply system:
General ............................. .-..............43a, b 31
Preparing for service ...... 43c 32
Testing ............. ......................................................................................46 34
Fuel tank:
Installing............................................................... 55j, 94a 44,87
Removing .........................................................................................55a, 79h 41, 72
Fuel tank cap assembly .................................................._.................... 11c 11
Fuel tank fittings .................................................................................. 44 32
Gapping:
Piston rings z...... ...... .... ................ 93i 84
Spark plugs .................................... 42d 31
Gasoline. (See Engine fuel.)
Gauge, oil filler...........,............................... 12 11
Gear, crankshaft:
Installing*.—........................................._........................... „.............. 93f 84
Removing .... ............. -......-.......... -........... -................—... 80i 76
115
TM 8-630
X-RAY FIELD UNIT GENERATOR
Gearcase: Paragraph Page
Installing .......... ............ ............................................................................93n 85
Removing .................................................................. 80f 76
Gearcase oil seal: ................ 93rn 83
Installing, Removing .......... 80g 76
Gears, clearance ............................................................................. "'78c, 80h 71, 76
General commutator:
Cleaning ...................................................................;.............................98b 89
Inspecting ...................................................................................... 55d, 100a 4i; 89
Sanding ....................................................................... 98c 89
Generator:
Cleaning .....................................................................................................98 89
Data .......... _......................................................................... 4a 8
Definition ..................... '//"54b, 96c 40,88
Disassembling ............................................................ 55a f 41
UCil©g ........................................................................ZZZZZ'L. 36a 26
Installing ..................................................................... 93q> 103c 86, 92
Models .......... -.................. ■..................................................................... 96b 88
Nomenclature ............................................................................. 54b 40
Performance ........................................................... ........... 4b 8
Reassembling .................................. ’ " S5j5103 44 91
Removing ......................................................................................... ’ 8ob ’73
Trouble shooting.............. ......................................................................... 3b 26
Generator ball bearing, lubricating ............................... ' 55; 44
Generator brushes:
Inspecting ....................... 55b 4j
Replacing ..................................................................................................55g 44
Generator brush springs:
Inspecting ................................................................................................55c 41
Replacing ..................................................................................................55h 44
Generator pole shoes, cleaning .....................................................................98b 89
Generator slip rings:
Cleaning .. ..................................................................................... ,... 98b 89
Inspecting ................................................ ,............................... .......-......55d 41
Sanding .......................... 98c 89
Generator support and bearing plate:
Cleaning ................................. <................. 85a 81
Inspecting ............................................................................................... 85b 81
Installing ................................................................................................. 93c 83
Removing ................................................................................................. 80n 77
Good condition, definition of ...................................................• 27c 15
Governor:
Cleaning .......................................................................................... 75a 67
Disassembling .................................................................................. 74b 66
function ......................................................................ZZZZZZZZZsb 61
Inspecting ...................................................................... 75b 67
Installing .................................................................... 76b 68
Parts, lubricating ................ . 73(j 67
Reassembling .......................................... ■................................Z Z..Z ..76a 68
Removing ....................................................................................... 74a 6l
Replacing .......................................................... ...................................... 7 5c 67
Governor and booster:
Adjusting ..............................................................................................77a, b 69, 70
Spring adjusting screw............. .......................... . _ Ilf 11
. Testing ...........................................................................ZZZZZZZ^b 70
Grinding valves ...................................................................... c>7 g^
Grounding:
Unit.......... ....... _.......................... 9(] 9
X-ray machine to unit ...................................................... 16 12
Guide and valve clearance ............................................ 78c 7]
Guide, valve, cleaning ................................................. 9la 8?
Hard starting ................................................................... Z ZZZZsa 23
Heads, cylinder:
Cleaning ............................................................................................83a 80
Inspecting ..................._........ ....... .............. 83b 80
Installing ..........................................................................................52d, 93o 37,85
Removing ............................. _...... ....... 52aj 80d 36j 73
116
TM 8-630
INDEX
Paragraph
Heating, generator ........................................................................................ „.36a
High mica ..................................................'....................................................100a
Holders, brush, cleaning ................................................. .......................„... 98d
Housing:
Blower:
Installing .... '........v......................................................... 93p
Removing ............................................ 80c
Cylinder air:
Installing . .............................. .............. _..........................52d, 95c
Removing ............................................................ .....................52 a, 80c
Identification:
Item ...........................................................................................................3b
Valves ...............................................................................................52c, 91a
Idle jet needle, carburetor ............... .................. .....,...................................11g
Ignition breaker:
Cleaning ...................................................................... 38c
Disassembling .................................................... 38b
Inspecting ................................................................................................38d
Reassembling ................................................,........................... .......... :.... 38g
Testing ............... ......... ......................... 40
Ignition breaker arm and points.............................. 38a
Ignition breaker box:
Installing .............. 94b
Removing ........................................ 79g
Ignition breaker points:
Refacing ....... ...................................................... 38c
Replacing ....... 38f
Setting gap.................................................................. 38h
Ignition system:
Description .................................................... :37b
Testing ...................... 72b
Inspecting new or used equipment ....................... .......................:................. 9c
Installing new or used equipment ................................. 9d
Intake manifold:
Installing ..... ....... 94c
Removing ........... 79f
Journals:
Camshaft:
Cleaning .................................................................................. 90a
Inspecting ........ r.................................................. 85b, 90b
Crankshaft:
Cleaning .................i...................................... i................ ’....89a
Inspecting .......................................................................85b, 88b, 89b
Kit, fuel pump ..................................... 63b
Lifters, valve:
Cleaning and inspecting ....................:........... 91
Installing .......... _....................... 93h
Removing ................;....... 80e
Lines:
Fuel:
Cleaning .... ................... ........................... .......................44d, 45b
Replacing ...........................................h............................. 1.....44d, 45b
Oil, OTC-38:
Cleaning ................................................ 81b
Inspecting ................. ................ 81c
List:
Abbreviations ....... .......................................................App.
All parts (SNL) reference.......... ........................................................App.
All service parts ............................. App.
Common parts, reference .................._................................................. App.
Forms ......... App.
Spare parts, reference ..................... App.
Standard nomenclature reference ............................ App.
Tools .......... —.................... App.
Tool kit, reference .............. ......................... ........._......... App.
Page
26
89
89
86
73
37, 88
36, 73
1
37, 82
11
27
27
27
27
30
27
87
72
27
27
30
27
60
9
9
87
72
82
81, 82
82
81,82
52
82
84
76
34
34
79
79
93
93
93
93
93
93
93
93
93
I 17
TM 8-630
X-RAY FIELD UNIT GENERATOR
Location in: Paragraph Page
Extreme cold ........................................................................................... 20c 13
Extreme heat .................... 21c 13
Lubrication ......................................................................... 26 15
Lubrication Order, WD .............................................................. 26 15
Lubricating:
Booster parts .............................................................................. 75h 67
Generator ball bearing ........ 55i 44
Governor parts ....... 75d 67
Magneto:
Adjusting ....................................................... 72a 60
Cleaning ................................................................ 70a 58
Disassembling ............... 69b 57
Inspecting ................................................................................................. 70c 58
Installing ............................................................................................. ......71b 58
Reassembling 71a 58
Removing ................................................................................................. 69a 57
Replacing 70d 58
Testing ...............................................40,72b 30, 60
Magneto coils:
Installing ..........................................................................................71a 58
Removing .................................................................... ........69b 57
Testing ............................................................................................. 70b, 72b 58, 60
Magneto condenser:
Replacing ......................................................................................... 41b 30
. Testing ............. 41a 30
Maintenance, preventive, second echelon .................................................... 33 19
Manifold, exhaust. (See Exhaust muffler.)
Manifold, intake:
Installing .......... T..................................................................................... 94c 87
Removing ................ ,................................................................................79f 72
Manual choke control ............................................................ nd n
Manufacturer ............................ 3d 8
Medical Supply Catalog reference .... .......................................App. 93
Mica, high ........ ................................................................................... 36b, 100a 26, 89
Mica, undercutting .................................................................................. 102 91
Models ........................................................................................................... 3c 1
Mounting generator ...........................................................................93q, 103c 86, 92
Muffler. (See Exhaust muffler.)
Needle, idle jet, carburetor ............................................ ng u
No. spark ......................................................................................................... 35g 25
Noise in brushes ....................... 36c 26
Nomenclature List, Standard, reference .................................................. App. 93
Oil base:
Cleaning ................................................................................................ ...86a 81
Inspecting ............................................................................................... 86b 81
Installing .................................................................................................93k 85
Removing 80j 76
Oil, engine:
Capacity .............................................................................. ..........,...4c 8
Excessive consumption ....... ..................... .........._.....................................35d 24
Specification ....:....................... 26 15
Oil filler gauge...... :.................................................................... ......................12 n
Oil lines, OTC-38:
Cleaning ............................................................................................81b 79
Inspecting ...... sic 79
Oil pan. (See Oil base.)
Oil pasages, OTC-38B, cleaning ................ 85a 81
Oil pump, OTC-38:
Cleaning .................................................. ‘...................................... sib 79
Disassembling ......................................................................................... 81a 77
Inspecting ............................................................ ...r................................. 81c 79
Operational inspection .............................................. _.... 81e 79
Reassembling .............................................................. ................. .......... 8 Id 79
Removing ........................................................;........._....._...... . ..............80k 77
Replacing ............................................................................ ....................93d 84
118
TM 8-630
INDEX
Oil pump, OTC-38B: Paragraph
Cleaning ........................................................................... _.. ................... 82b
Disassembling .... ....................................................... ........... ;....... 82a
Inspecting ,.......................................................... 82c
Reassembling ..................................................... 1................ .................. 82d
Removing ................. 801
Replacing ..................................................... .............................................93e
Oil seal, crankshaft:
Replacing ..................................................... 1.....................................93b
Removing ................................................................................................. 80o
Oil seal, gearcase:
Replacing .......................... .................. 93m
Removing .......... 80g
Operation under:
Dust and sand ............................................................. 22
Extreme cold ..............................................................................................20
Extreme heat .............................................................. .................. ............. 21
During usual conditions ............. ........................... ... .13, 14, 15, 16, 17
Outlet, conductor cable:
Installing .........................................................................................103d
Removing ........................... 97b
Overheating:
Engine ............................................................................ 35c
Generator ........................ ........................................... ...................,..........36a
Pan, oil. {See Oil base.)
Part lists:
All service ...... App.
Common, reference ..................................................................... App.
SNL, reference ............................................................................ App.
Spare, reference ......................................................... App.
Parts:
Second echelon ............................................... 6b
With unit................................................................ .................................... ...............6a
Passage, oil, OTC-38B, cleaning .................................... 85a
Performance, engine and generator ............................................................... 4b
Petcock, shut-off:
Cleaning ......... .'......................................................................................... 44c
Flushing ............................ ......................................... 44e
Pin, valve, inspecting ............................................................................... 91b
Pinging.......;.................................................................................................... 35h
Pipe, exhaust .................. :....................... ............................................. 9d
Piston pin:
Inspecting ................................................................................ 88b
Clearances .... :............... ............................................................... 78c
Piston ring:
Gapping ............................... 78c, 93i
Installing ..................................................................................................93i
Positioning ................................. 93j
Pistons:
Cleaning .......... _.......................................................................................87a
Disassembling ....;................................. 80m
Inspecting ................................... »............................................................ 87b
Installing ........... 93j
Reassembling ...... .......... 93i
Removing ............................................................................................. 80m
Plate, bearing. {See Bearing plate and generator support.)
Plate, brush. {See Brush rig.)
Plugs. {See Spark plugs.)
Points:
Inspecting ........................................................................................ 38d
Refacing ....... 38c
Setting gap ....... 38h
Page
80
79
80
80
77
84
83
77
85
76
13
13
13
11, 12
92
88
24
26
93
93
93
93
8
8
81
8
34
34
82
25
9
82
71
71, 84
84
85
81
77
81
85
85
77
27
27
30
I 19
TM 8-630
X-RAY FIELD UNIT GENERATOR
Paragraph Page
Pole shoes, cleaning ........................................... ............................................ 98b 89
Popping ............................................ ................................................................ 35h 25
Preparation for shipment and storage .......... ■.....................App. 93
Preventive maintenance ..................................................................... 33 19
Pump, fuel. (See Fuel pump.)
Pump, oil. (See Oil pump.)
Records ............................................................................................. 2 1
References ....................................................................................................App. 93
Remounting generator .......................................................................... 93q, 103c 86, 92
Removing carbon .............. ............................................................................ 52b 36
Retainer, valve spring, inspecting .......................................................... 91b 82
Rig, brush. (See Brush rig.)
Rings, piston. (See Piston rings.)
Rocker arm, oil pump OTC-38, inspecting ..... 81c 79
Rods, connecting. (See Connecting rods.)
Running test ................................................................... r._.............................................33d 19
Sanding, commutator and slip rings ............................................................. 98c 89
Screen:
Breather tube, cleaning and replacing ..................................... ,........... 49a 35
Fuel pump, cleaning and replacing ............................................... 45a 34
Oil pump OTC-38 :
Cleaning .................................................................................... 81b 79
Inspecting .........................................................................................81c 79
Oil pump OTC-38B:
Cleaning ..... 82b 80
Inspecting ..........................................................................................82c 80
Screw, filler cap shut-off ............................................... 11c 11
Seals, oil. (See Oil seals.)
Seat, valve:
Grinding................................ :................................................................... 92 83
Inspecting .............................................. 91b 82
Width ...................................................................................... 78c 71
Second echelon:
Preventive maintenance ............. 33 19
Spare parts ................................................................................................. 6b 12
Secure, definition of ......................................................................................27e 15
Service:
After operation ............ 32 17
At stop ...................•.................................................................................... 31 17
Before operation ...................... 29 16
Definition of ......................... 33b 19
During operation ............. 30 16
Service parts:
For model OTC-38 .......................................................................... App. 93
For model OTC-38B............................................................................. App. 93
Interchangeable .....................................................'............ ......App. 93
Shipment ............................... App. 93
Shoes, pole, cleaning .... .............................................. 98b 89
Short circuit in conductor cable or X-ray machine ...................................35b 23
Shut-off:
Petcock: ■<
Cleaning ................................................... .-.... .... .............. ..........44c 34
Flushing ...................... >........................... 44e 34
Screw: filler cap ....... 11c 11
Slip rings:
Cleaning ....... 98b 89
Inspecting ......................................................................................55d, 100b 41, 89
Sanding .....................................................................................................98c 89
Spare parts:
List, reference ................... App. 93
Second echelon ................................... ;............... 6b 8
With unit................................................ 6a 8
120
TM 8-630
INDEX
Paragraph Page
Spark knock.................................................... 35h 25
Spark plug cables, cleaning and inspecting ................... 39 , 30
Spark plugs:
Cleaning .................................. 42b 31
Inspecting .................................................................................................42 c 31
Removing .............................. 42a 30
Replacing .................................................................................................42 f 31
Resetting gap ..........................................................................................42d 31
Testing ..................................... 42e 31
Spark, weak .............................................. .'..... _.................................. 35g 25
Specification for:
Engine fuel ............................................................................................. 29b 16
Engine oil ................................................................... 26 15
Exhaust vent ................................................................... 9d 11
Spitting .................._..... 35h 25
Spring adjusting screw, governor-booster ..................... Ilf 11
Spring, oil pump OTC-38:
Cleaning ...................................................................................................81b 79
Inspecting .................................... 81c 79
Springs, brush:
Inspecting ................................................................................................. 55c 41
Replacing ................................................................................................. 55h 44
Springs, valve:
Inspecting ..........................................................................................91b 82
Installing .............................................................. 93g 84
Removing ................................................................................................. 80e 76
Standard Nomenclature List, reference ................. ,.App. 93
Starting ........... _.........................................................................14 11
Stop button ........................................................ :............................................He 11
Stopping ................................................................... .........................................17 12
Storage ................................................................................ App. 93
Tank, (See Fuel tank.)
Tappets:
Adjusting .......................................... 52c 3'
Clearances ................................................................. ............................................78c “ 1
Technical Manual references ..................................................... App. 93
Temporary storage ...__ ___ ....... ..................................................................... .. App. 93
Testing:
AC winding ............................. ’..101c 91
Booster and governor ...... 77b 70
Breaker and magneto ..............'........................ 40 30
Carburetor ............ _................. 62b 52
Compression ............................................ _................ 53 40
Condenser, magneto ......................................................................... 41a 30
DC winding............................................................................................ 101b 91
Engine ..... 33d 19
Field coils ................................................... lOld, e 91
Fuel pump ..................................................................... 67b 57
Fuel supply system ..................................................................................46 34
Governor and booster ............................................... 77b 70
Ignition system . 72b 60
Magneto .......................................................1...........................................72b 60
Magneto coils ...............................................................................70b, 72b 58,60
Spark plugs ............................................................................................. 42e 31
Tightening:
Cylinder heads ....................... ....................................... 52d 37
Definition of ......... 33b 19
Timing, adjusting ignition ............. 72a 60
Tool kit list, reference ................................................................................ App. 93
Tool list .................................................................................................... App. 93
Tools with unit ....... ...._.............................5 8
Trouble shooting:
Engine .....................................—.........................—.............................. 35 23
Generator ............... :................................................... 36 26
121
TM 8-630
X-RAY FIELD UNIT GENERATOR
Tube and screen, breather: Paragraph
Cleaning .................. 49a
Installing ................................................................................................. 94d
Removing ............................................................................................... 79e
Replacing ..................................................................................... 49a
Unpacking ..... 9a
Unusual operating conditions ......................... :......... 19
Valves:
Adjusting tappets ....... 52c
Cleaning .............................................................. 91a
Grinding ............. 92
Identifying .......... .................... ....................................................52c, 91a
Inspecting .................................. 91b
Removing ......................................................... 80e
Replacing ................. 93g
Valve guides, cleaning ................................................ 91a
Valve lifters:
Cleaning and inspecting ... .... ................ ....... 91
Installing .................. 93h
Removing ........,.......................... 80c
Valve pins, inspecting ........................................................................ 91b
Valve seat width ............. 78c
Page
35
87
72
35
9
12
37
82
83
37, 82
82
76
84
82
82
84
76
82
71
Valve seats:
Grinding..................... .................. . ....................................................................... ......... 92 83
Inspecting ______ _ _____ __ ___ .......-........................................................... .......91b 82
Valve springs:
Inspecting ................................... ...................................................................... .......91b 82
Installing .................................................... .......93g 84
Removing ...................... .......... 80e 76
Valve washers, inspecting .. ............................ ....................................................................... .9 lb 82
Valve tappets, adjusting ...... ..... 52c 37
Vent:
Exhaust ... ................................................... ......... 9d 9
Filler cap ........... ........................................ .......44b 32
Ventilation ......................................................... ... 9d 9
WD circulars, references .....................’............. .. App. 93
WD Lubrication Order ................................... ...... 26 15
Warm-up under:
Extreme cold ............................................. .... 20b 13
Extreme heat ................................:.............. 21b 13
Usual conditions ............................................................................................................ ........ 15 12
Washers, valve, inspecting ........................ ...... 91b 82
Weak spark ........................................................ 35g 25
X-ray machine:
Connecting .. . ....... ....................... ....... ..........16 12
Disconnecting ........................................... .............................. ......................................... .......17a 12
Item numbers ............................................. ......................................1................................ ..........18 12
☆ U. S. GOVERNMENT PRINTING OF! 192
122

a
UNT LIBRARIES DENTON TX 7JM3
1001895565