Chapter XXVI: Section XXV: Tires, Wheels, and Hubs

Paragraph
Description 122
Tires 123
Rims and spokes 124
Front wheel replacement 125
Front wheel hub adjustment 126
Rear wheel replacement 127

122. DESCRIPTION.

=a.= Wheels have drop center rims to accommodate 4.00 x 18 tires. Front and rear wheels are not interchangeable. Front wheel hub is of ball‐bearing design, having cone adjustment similar to that of a bicycle hub. Rear wheel hub is of roller‐bearing design and must be taken apart for adjustment. Both wheels have “knock‐out” type axles.

123. TIRES.

=a. Description.= Wheel rims are of the drop‐center type, having a depression, or well, in center of rim. The rim well, being smaller in circumference than the rest of the rim, allows one casing bead to fit loosely in it while other bead is being worked over edge of rim. Bear in mind the importance of keeping one bead in rim well while other bead is being worked onto or off rim. NOTE: _It is not always necessary to completely remove casing from rim. Removing one side only allows inner tube to be removed and reinstalled, and also allows inside of casing to be inspected._

=b. Remove.=

(1) Remove wheel from vehicle and lay wheel on its side. To remove front wheel, refer to paragraph 125. To remove rear wheel, refer to paragraph 127.

(2) Remove valve cap and valve core to free all air from tube.

(3) Press casing head into rim well to within a short distance of each side of valve.

(4) Using tire iron “B” in vehicle kit (fig. 11), start bead over edge of rim at valve. Do not use force when starting bead over edge of rim with tire iron, because bead wires may be broken or stretched, and tire ruined. With first bead in rim well, bead on other side can be started easily over edge of rim. After a portion of second bead is started over rim edge, casing can be further removed from wheel without aid of tire iron.

_Figure 81—Disassembly for Front Wheel Removal_]

=c. Install.= Before applying casing to rim, see that rubber rim strip is in place in rim well and that rim strip valve hole alines with valve hole in rim.

(1) Start either bead of casing over rim edge. Work around wheel until entire bead is on rim.

(2) Place inner tube in casing. NOTE: _Inner tube may be placed in casing before or after first bead of casing is on rim._ Insert valve stem through hole in rim and start valve stem lock nut. While pressing first bead into rim well, work remaining bead over edge of rim, starting directly opposite valve stem. Work both ways around wheel toward valve.

(3) Inflate front tire to 18 pounds, and rear tire to 20 pounds.

(4) Reinstall front wheel (par. 125): reinstall wheel (par. 127). CAUTION: _Tire casings are balanced and must be applied to rim with balance mark located at valve stem. On Firestone tires the balance mark is a red triangle, and on Goodyear tires a red dot._

124. RIMS AND SPOKES.

=a.= Wheels with broken and or missing spokes, with rims in badly kinked and or distorted condition, or having considerable run‐out, must be replaced.

=b.= Loose wheel spokes must be tightened evenly, being careful not to distort rim out‐of‐round or cause run‐out. Use spoke nipple wrench (41-W-3339) for front wheel spokes, and wrench (41-W-3340) for rear wheel spokes.

=125. FRONT WHEEL REPLACEMENT= (fig. 81).

=a. Remove.=

(1) Support vehicle on rear stand. Raise front end of vehicle by blocking up under frame loop on skid plate.

(2) Remove brake shackle bolt from rigid fork on left side of vehicle.

(3) Front axle is knock‐out type. Remove cotter pin and axle castle nut and pull out axle. Wheel is free for removal. CAUTION: _Before removing axle note how slot in brake stabilizer plate is fitted over the extended (button) end of the left‐front rocker plate stud. It is necessary that this be correctly assembled when replacing front wheel._

(4) Roll wheel forward and remove brake assembly from brake drum, leaving the assembly attached to brake control wire and control wire housing.

=b. Install= (fig. 81). NOTE: _At the time wheel and brake assembly is located in front fork, and before axle is installed, make sure that the curved slot in brake stabilizer plate engages with the button end of the left‐front rocker plate stud._

(1) Install brake assembly in brake drum.

(2) Roll wheel into position. Engage stabilizer plate notch and rocker plate stud button end, and at same time insert front axle.

(3) Install castle nut (no lock washer used) on axle and securely tighten.

_Figure 82—Front Hub Prepared for Cone Adjustment_]

(4) Use good cotter pin to secure nut.

(5) Install brake shackle bolt and special lock washer and nut. Tighten nut.

(6) Check front brake control wire and housing to make sure everything is in order and correctly adjusted (par. 97).

(7) Remove blocking from under vehicle.

126. FRONT WHEEL HUB ADJUSTMENT.

=a.= Front wheel, ball‐bearing hub, is similar to a bicycle front hub as far as adjustment is concerned. Do not completely disassemble hub for adjustment as balls are not in retainers, and will fall out when cone is removed. Hub is provided with grease deflector sleeve and felt retainer. NOTE: _Earlier models are not equipped with grease deflector sleeve or felt retainer washer. Front wheel should have slight play or shake on bearings, and should turn freely._

_Figure 83—Disassembly for Rear Wheel Removal_]

(1) Remove front wheel (par. 125).

(2) Back off cone lock nut to end of axle sleeve. Do not remove nut.

(3) Turn cone on axle sleeve to the right (clockwise) to take up wheel play, and to the left (counterclockwise) to give more wheel play. Adjust so that wheel has slight play on bearing.

(4) Tighten cone lock nut. After tightening nut, again try for slight wheel play on bearing. Sometimes tightening lock nut takes up on bearing play. If necessary, readjust for desired results when cone lock nut is tight.

(5) Install front wheel and brake assembly (par. 125).

(6) Check adjustment of front brake.

=127. REAR WHEEL REPLACEMENT= (figs. 83 and 84).

=a. Remove.=

(1) Support vehicle on rear stand.

(2) Release mudguard rear stays. Loosen mounting nuts, and raise end of mudguard for wheel clearance.

_Figure 84—Brake Rod Lock_]

(3) Remove the five wheel mounting socket screws which secure wheel hub to brake shell and sprocket assembly. Use vehicle kit wrench “S” and sleeve (handle) “C” (fig. 11). NOTE: _Wrench can be inserted from left side through holes in hub, and wheel must be turned to bring each mounting screw directly to the rear of axle for accessibility._

(4) Use brake rod lock to set and lock brake to prevent brake shell and sprocket from coming off brake assembly while wheel is being removed. Apply brake pedal and shift brake rod lock against tool box bracket, securing lock in this position with wing nut (fig. 84).

(5) Remove axle nut (right side of vehicle), using vehicle kit wrench “J” (fig. 11).

(6) Pull out axle from left side of vehicle.

(7) Remove spacer from between wheel hub end and left side of frame.

(8) Wheel is now free to come out by pulling and working it away from dowel pins located in brake shell assembly. A wheel being removed for the first time may offer some resistance. It will be observed that chain, sprocket, and brake assembly remain in the vehicle frame.

=b. Install= (figs. 83 and 84).

(1) Position wheel on brake shell dowel pins. Work hub onto dowels as far as it will go.

(2) Install axle spacer at left end of hub so that axle will pass through it and the hub.

(3) Install axle from left side of vehicle. Pass it through sleeve and hub, with end of axle engaging the frame left axle clip notch.

(4) See that lock washer is in place. Turn on and securely tighten axle nut, using vehicle kit wrench “J” (fig. 11).

(5) Loosen wing nut clamping brake rod lock. Move brake rod lock forward so that it will not strike any object when brake is operated; tighten wing nut to retain in position (fig. 84).

(6) Install and securely tighten the five wheel mounting socket screws.

(7) Lower mudguard into position and attach ends of rear stays. Securely tighten the clamping nuts.

REFERENCES

STANDARD NOMENCLATURE LISTS
Motorcycle, chain drive (Harley‐Davidson) SNL G-523

Cleaning, preserving and lubricating materials,
recoil fluids, special oils, and miscellaneous
related items SNL K-1

Soldering, brazing, and welding materials, gases,
and related items SNL K-2

Tools, maintenance, for the repair of automotive
vehicles SNL G-27

Tool sets—motor transport SNL N-19

Tool sets for ordnance service command, automotive
shops SNL N-30

Current Standard Nomenclature Lists are listed above.

An up‐to‐date list of SNL’s is maintained in the
Index to Maintenance Publications OFSB 1-1

EXPLANATORY PUBLICATIONS
Military motor vehicles AR 850-15

Automotive Materiel
Automotive electricity TM 10-580
Electric fundamentals TM 10-455
The motor vehicle TM 10-510
Chassis, body, and trailer units TM 10-550

Maintenance and Repair
Automotive lubrication TM 10-540
Motor transport inspections TM 10-545
Tire repair and retread TM 9-1868
Cleaning, preserving, lubricating and welding
materials and similar items issued by the
ordnance TM 9-850
Detailed lubrication instructions for ordnance
materiel OFSB 6-series

Protection of Materiel
Explosives and demolitions FM 5-25
Defense against chemical attack FM 21-40
Decontamination of Armored Force vehicles FM 17-59
Chemical decontamination, materials and equipment TM 3-220

List of Publications for Training FM 21-6

Storage and Shipment
Registration of motor vehicles AR 850-10
Storage of motor vehicle equipment AR 850-18
Ordnance storage and shipment chart,
group G—Major items OSSC-G

INDEX

A Page No.

Air cleaner, 122

Allocation of maintenance by echelons, 40

Ammunition box carrier, 169

Armature bearing special lubrication, 145

Auxiliary brake, 12

B

Battery, lighting system, horn
battery
check electrolyte level, 181
installation, 185
removal, 181
description, 181
horn
adjustment, 190
description, 190
ignition and light switch
installation, 188
removal, 188
service headlights
adjustment, 185
blackout, 186
marker, 187
taillights
blackout stop and taillight, 187
service stop and taillight, 187
wiring
cable system, 190
removal and installation, 190

Brake system
brake shoe installation, 151
brake shoe removal, 150
front wheel brake, 151
rear wheel brake
adjustment, 149
linkage, 149

C

Carburetor
adjustment, 116
bowl cleaning, 120
installation, 118
removal, 118

Chains and sprockets
chain oilers, 109
chain repair tool, 113
countershaft sprocket replacement, 114
engine sprocket replacement, 113
front chain adjustment, 105
front chain replacement, 111
rear chain adjustment, 107
rear chain replacement, 111
rear wheel alinement, 107

Clutch
control adjustment, 85
description, 86
disk and spring inspection, 91
disk installation, 93
disk removal, 90
maintenance and adjustment, 86
release bearing
installation, 95
removal, 95
spring tension adjustment, 89

Controls and operation
controls
auxiliary brake (front wheel), 12
carburetor choke, 13
clutch, 10
foot starter crank, 12
gasoline valve, 9
gear shifter, 12
ignition and light switch, 12
instrument panel signal lights, 13
service brake (rear wheel), 12
spark, 10
steering damper, 12
throttle, 10
driving precautions
avoid low gear operation, 17
braking, 17
high‐speed tips, 17
engine prestarting instructions, 13
operation of vehicle
starting on level ground, 16
starting on uneven or soft ground, 16
running‐in new engine (or vehicle), 19
starting engine
behavior of instrument panel signal lights, 15
cold engine, 14
engine with dead battery, 15
hot engine, 15
warm engine, 14
stopping and parking vehicle
parking vehicle, 18
stopping vehicle, 17
stopping the engine, 16
towing vehicle to start engine
engine starting with dead battery, 18

D

Data, tabulated
engine, 72
vehicle specifications, 7
capacities, 8
performance, 7

Description
battery, lighting system, horn, 181
clutch, 86
engine, 72
generating system, 142
ignition system, 129
intake and exhaust system, 122
tires, wheels and hubs, 193
transmission, 96

Description of vehicle, 7

E

Echelon system of maintenance allocation, 40

Engine
carbon removal, 74
data, 72
description, 72
head, gasket replacement
installation, 74
removal, 73
installation, 82
oil feed pump replacement, 77
removal, 78
tune‐up, 72
valve tappet adjustment, 74

Exhaust system, 126

F

First echelon preventive maintenance services
after‐operation and weekly service, 25
at‐halt service, 24
before‐operation service, 21
during‐operation service, 23
purpose, 20

Fuel system
carburetor
installation, 118
removal, 118
carburetor adjustment
complete readjustment of carburetor, 116
low speed adjusting needle, 116
carburetor bowl cleaning, 120
fuel pipe
installation, 121
removal, 121
fuel strainer
cleaning, 120
install strainer assembly, 120
remove strainer assembly, 120
general, 115
throttle control wire adjustment
closed throttle, 118
open throttle, 118

G

Generating system
armature bearing special lubrication, 145
commutator cleaning, 143
cut‐out relay, 147
description, 142
generator installation, 147
generator removal, 145

Generator removal and installation, 145, 147

H

Horn, 190

I

Ignition system
circuit breaker and timer assembly installation, 133
recommended recheck of ignition timing, 135
removal, 133
circuit breaker points
adjustable contact point installation, 131
adjustable contact point removal, 131
adjustment, 131
breaker lever installation, 131
breaker lever removal, 130
coil to timer wire
installation, 138
removal, 138
condenser
installation, 133
removal, 131
description, 129
spark coil
installation, 140
removal, 139
spark control adjustment, 139
spark plugs
cleaning, 129
point adjustment, 129
replacement, 129
type, 129

Installation procedure
air cleaner, 126
ammunition box carrier, 169
battery, 185
battery box, 173
carburetor, 118
circuit breaker and timer assembly, 133
circuit breaker lever, 131
circuit breaker points, 131
clutch release bearing, 95
coil to timer wire, 138
condenser, 133
control wire housings, 166
engine, 82
engine head gasket, 74
exhaust pipe, 127
foot starter, 98
fork assembly, 158
front wheel, 196
fuel pipe, 121
fuel strainer assembly, 120
fuel tank, 175
generator, 147
handle bar assembly, 163
ignition and light switch, 188
instrument panel cover, 191
jiffy stand, 177
luggage carrier, 170
mudguards, 171
muffler assembly, 127
oil tank, 176
outer front chain guard, 167
rear chain guard, 169
rear stand, 176
rear wheel, 199
saddle post, 178
safety guards, 178
scabbard carrier, 169
skid plates, 180
spark coil, 140
spark control wire, 166
speedometer, 192
spring forks, 154
starter crank springs, 101
steering damper, 161
throttle control wire, 165
tires, 195
tool box and bracket assembly, 173
upper bumper springs, 155
upper coil springs, 155
wiring, 190

Instrument panel
indicator lights, 191
panel cover
installation, 191
removal, 191
speedometer
installation, 192
removal, 192

Intake and exhaust system
air cleaner
general, 122
installation, 126
maintenance, 123
removal, 125
service, 122
air cleaner mounting bracket replacement, 126
description
exhaust, 122
intake, 122
exhaust system
muffler assembly installation, 127
muffler assembly removal, 126
pipe installation, 127
hose and carburetor fitting
installation, 125
removal, 125

Introduction
scope of manual, 3
supersession of quartermaster manuals, 3

L

Lighting system, 181

Lubrication
introduction, 30
lubrication guide, 30
general, 30
lubrication notes, 30
oilcan points, 34
supplies, 30
warning light, 34

M

Maintenance allocation
allocation of maintenance by echelons
clutch, 40
controls and linkage, 40
electrical group, 41
engine (V‐45″ twin engine), 41
exhaust group, 42
miscellaneous, 42
suspension (front), 43
suspension (rear), 43
tires, 44
transmission, 44
vehicle assembly, 44
scope of maintenance, 39

Manual, scope of, 3

O

Organization tools and equipment, 60

P

Preventive maintenance services
first echelon, 20
second echelon, 45

R

References
explanatory publications
automotive materiel, 200
list of publications for training, 200
maintenance and repair, 200
protection of materiel, 200
storage and shipment, 200
standard nomenclature lists, 200

Removal procedure
air cleaner, 125
ammunition box carrier, 169
battery, 181
battery box, 172
carbon, 74
carburetor, 118
circuit breaker and timer assembly, 133
circuit breaker lever, 130
condenser, 131
control wire housings, 166
engine, 78
engine head gasket, 73
foot starter, 98
fork assembly, 155
front wheel, 195
fuel pipe, 121
fuel strainer assembly, 120
fuel tank, 174
generator, 145
handle bar assembly, 162
ignition coil to timer wire, 138
instrument panel cover, 191
jiffy stand, 176
luggage carrier, 170
mudguards, 170, 171
muffler assembly, 126
oil tank, 175
outer front chain guard, 167
rear chain guard, 169
rear stand, 176
rear wheel, 198
release bearing (clutch), 95
saddle post, 178
safety guards, 178
scabbard carrier, 169
skid plates, 180
spark coil, 139
spark control wire, 166
speedometer, 192
spring forks, 154
starter crank spring, 98
steering damper, 161
throttle control wire, 164
tires, 193
tool box and bracket assembly, 173
upper bumper springs, 155
upper coil springs, 155

Road test chart of maintenance operations, 49

S

Second echelon preventive maintenance
road test chart, 47
maintenance operation, 49
services
first echelon participation, 45
frequency, 45
general procedures, 45
specific procedures, 47

Sheet metal and equipment
battery box
installation, 173
removal, 172
carriers
ammunition box carrier installation, 169
ammunition box carrier removal, 169
fuel tank
installation, 175
removal, 174
chain guards
outer front chain guard installation, 167
outer front chain guard removal, 167
rear chain guard installation, 169
rear chain guard removal, 169
jiffy stand
installation, 177
removal, 176
luggage carrier
installation, 170
removal, 170
mudguard (front)
installation, 171
removal, 170
mudguard (rear)
installation, 171
removal, 171
oil tank
installation, 176
removal, 175
rear stand
installation, 176
removal, 176
saddle post
description, 178
installation, 178
removal, 178
safety guards
installation, 178
removal, 178
scabbard carrier
installation, 169
removal, 169
skid plates
installation, 180
removal, 180
tanks
fuel tank, 173
general, 173
oil tank, 173
tool box
box and bracket assembly installation, 173
box and bracket assembly removal, 173

Spark plugs, 129

Speedometer
installation, 192
removal, 192

Steering control
control wire housings
installation, 166
removal, 166
fork assembly (complete)
installation, 158
removal, 155
rocker plate studs, 160
forks (springs)
installation, 154
removal, 154
handle bar controls
install throttle control wire, 165
remove throttle control wire, 164
handle bars
installation of assembly, 163
removal of assembly, 162
spark control wire
installation, 166
removal, 166
steering damper
installation, 161
removal, 161
upper coil springs and upper bumper springs
installation, 155
removal, 155

Stowage on vehicle (tools and equipment), 35

T

Tabulated data
engine, 72
vehicle specifications, 7
capacities, 8
performance, 7

Tires, wheels, and hubs
description, 193
front wheel
hub adjustment, 197
installation, 196
removal, 195
rear wheel
installation, 199
removal, 198
rims and spokes, 195
tires
description, 193
installation, 195
removal, 193

Tools and equipment stowage on the vehicle
vehicle equipment, 36
vehicle spare parts, 38
vehicle tools, 35

Transmission
control linkage
adjustment, 97
checking gear shifter control linkage, 96
transmission shifted to adjust front drive chain, 96
description, 96
foot starter
installation, 98
removal, 98
installation, 101
removal, 99
starter crank springs
installation, 98
removal, 98

Trouble shooting
brakes, 70
electrical system, 68
engine
instruction, 61
tests to determine mechanical condition, 63
engine lubricating system, 64
fuel system, 65
generating system, 68
ignition system, 66
introduction, 61
steering, 71
transmission and clutch, 69
wheels and chains, 69

W

Wheels and hubs, 195

Wiring, 190

[A.G. 300.7 (17 Aug. 1943)]

BY ORDER OF THE SECRETARY OF WAR:

G. C. MARSHALL,
_Chief of Staff_.

OFFICIAL:
J. A. ULIO,
_Major General_,
_The Adjutant General_.

DISTRIBUTION: R9 (4): IR 5, 7 and 17 (5): Bn 9 (2): IBn 5, 6,
7 and 17 (5): C9 (8): IC 5, 6, 7 and 17 (5)

(For explanation of symbols, see FM 21-6)

RAPD3OEC43-81M

PUBLICATIONS DEPARTMENT ‐ RARITAN ARSENAL

Transcriber’s notes:

In the Fig. 51 caption M—MARK ON BREAKER CAM AND MARKS ON TIMER HEAD AND HAND - ‘HAND’ should possibly read ‘BAND’.

In the echelon table, section 25. ALLOCATION OF MAINTENANCE, ‘strained gasoline’ should possibly read ‘strainer gasoline’.