Jeep Willys 1944 User Manual

WAR DEPARTMENT TECHNICAL MANUAL

TM 9-803

%-TON 4x4 TRUCK

(WILLYS-OVERLAND

MODELMB and

FORDMODELGPW)

WAR DEPARTMENT .

Washington : 1947

FEBRUARY 1944

WAR DE?ARTMENT

Washington 25, D. C., 22 February 1944

TM 9-803, J/4-ton 4 x 4 Truck (Willys-Overland Model MB and Ford
Model GPW), is published for the information and guidance of all
concerned.

[A. G. 300.7 (17 November 43))

BY ORDEROFTHESECRETARYOFWAR:

G. C. MARSHALL,

Chief of Staff.

OFFICIAL:

’ J. A. ULTO,

Major General,

The Adjutant General.

DISTRIBUTION:C&H (1).

(For explanation of symbols, see FM 2 l-6)

2

%K!TION 1

II

III

IV

. VI

VII

TRUCK (WILLYS-OVERLAND

and KbR0 MODEL GPW)

CONTENTS

Introduction. . . . . . . . . .

Dcacription and tabulated data.
Driving control8 and operation. .

Operation under unusual

conditiona..................

First echelon preventive

V

maintenance service. . . . . . .

Lubrication. . . . .

Tools and equipment stowage on

the vehicle. . . . . . . . . .

TM 9-803

pmmgraphr Pmges

1 5-9
2-3 10-12
4-6 13-20

7-11

12-16
17-18

19-21 49-5 1

21-27

28-36
37-48

CART TWO-VEHICLE MAINTENANCE INSTRUCTIONS

SICTION VIII

IX

XI

XII

XIII

XIV

xv

XVI

XVII

XVIII

XIX

Record of modifications. . . .

Second echelon preventive

,

maintenance. . . . . . . . .

New vehicle run-in test. . . .

X

Organization tools and

equipment. . . . . . . . .

Trouble shooting. . . . . . . .

Engine-description, data,

maintenance, and adjustment

in vehicle. . . . . . . . .

Engine-removal and installation

Ignition system. . . . . . . . . .

Fuel and air intake and exhaust

systems....................

cooling system . . . . . . . .

starting nystem . . . . . . . . . . . .

Generating system. . . . . . . . . . . .

3

22

23

24-26

27-28
29-49

50-59 104-115
60-61 116-117
62-69 118-125

70-78 126-136
79-86 137-143
87-90 144-145
91-94 146-149

53-67
68-72

74-103

52

73

TM 9-803

l/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

SECTION XX

XXI

XXII

XXIII

XXIV

xxv

XXVI

XXVII

XXVIII

XXIX

xxx

xxx1

xxx11

Battery and lighting system. . 95-106

Clutch....................... 107-112

Transmission. . . . . . . . 113-116

Transfer case.. . . . . . . . 117-121

Propeller shafts and universal

joints...................... 122-125

Front axle.. . .!. . . . . 126-137

Rear axle.. . . . . . . . . . 138-145

Brakes....................... 146-152

Springs and shock absorbers. 153-157

Steering gear. . . . . . . . . 158-l 63

Body and frame.. . . . 164-175

Radio interference suppression

system..................... 176-179

Shipment and temporary storage 180-182

Paragraphs

Pages

150-166
167-171
172-175
176-178

179-180
181-188
189-192
193-204

205-210
211-215
216-220

221-227

228-232

REFERENCES. . .

INDEX...............................................

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

233-234

235

4

TM

9-803

1

PART ONE-OPERATING INSTRUCTIONS

Section I

INTRODUCTION

Paragraph

Scope . . . . . . . . . . . . . . . . . . . . . . . . .._....................... 1

1. SCOPE.
a. This technical manual* is published for the information and

guidance of the using arm personnel charged with the operation and

maintenance of this materiel,

b. In addition to a description of the I/4-tori 4 x 4 Truck (Willys-

Overland model MB and Ford GPW), this manual contains technical
information required for the identification, use, and care of the mate­riel. The manual is divided into two parts. Part One, sections I
through VII, contains vehicle operating instructions. Part Two, sec-

Lf_-_ x1111 LL_^.._.l_ “VVIT ^__L_:__ _._L:_,_ __:_e___,,, :_“C....,.C:~^..

Ll”rlS ” 111 rrll”uyrl **All, C”,,LIll,S “C,,,CK ,‘,alllLcllaL,L.c lllDl.l ULLl”llJ
to using arm personnel charged with the responsibility of doing
maintenance work within their jurisdiction, including radio suppres­sion and shipment and temporary storage information.

c. In all cases where the nature of the repair, modification, or

adjustment is beyond the scope of facilities of the unit, the respon­sible ordnance service should be informed so that trained personnel
with suitable tools and equipment may be provided, or proper in­structions issued.

d. This manual includes operating and organizational mainte-

nance instructions from the following Quartermaster Corps lo-series

technical manuals. Together with TM g-180349 and TM 9-1803B,

this manual supersedes them:

,.\ mrr .I\ ..nrl nr\ .___.._A .nn.

llvl IV-lllJ.3, LU fwlgusr 1YLtl.

(11

(2) TM 10-1207, 20 August 1941.
(3) TM 10-1349, 3 January 1942.
(4) TM 10-1513, Change 1, 15 January 1943.

*To provide operating instructions with the materiel, this technical manual has

been published in advance of complete technical review. Any errors or omissions
will be corrected by changes or, if extensive, by an early revision.

Figure I--I/4-Ton 4 x 4 Truck-Left Front

RA PD 305251

f

INTRODUCTION

TM 9-803

1

0,

c

0

0

TM 9-803

1

l/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

8

INTRODUCTION

TM 9-803

1

TM 9-803

2-3

l/i-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

Section II

DESCRIPTION AND TABULATED DATA

Paragraph

Description .

Data _.._., .._.... .

2. DESCRIPTION.

mm._._ m,~?_ _~.,L_,_ .

a.

1 YPe*

carrier especially adaptable for reconnaisance or command, and
designated as I/d-ton 4 x 4 Truck. It is a four-wheel vehicle with
four-wheel drive. The engine is a 4-cylinder gasoline unit located in
the conventional place, under the hood at the front of the vehicle.
A conventional three-speed transmission equipped with a transfer

case provides additional speeds for traversing difficult terrain. The
body is of the open type with an open driver’s compartment. The
folding top can be removed and stowed: and. the windshield tilted
forward on top of the hood, or opened upward and outward. A spare
wheel equipped with a tire is mounted on thr rear of the body, and a
pintle hook is provided to haul trailed loads. Specifications of the

vehicle are given under “Data” (par. 3). Genrral physical character-

istics are shown in figures 1 through 4.

h. Identification. The manufacturer’s chassis serial number is
stamped on a plate inside the left frame side member at the front end,
and on the name plate (fig. 6). The engine serial number is stamped

on the right side of the cylinder block. front upper corner. The U.S.A.
registration number is painted on both sides of the hood.

~nls vemcle is a generai purpose, personnei, or cargo

2

3

3. DATA.

a. Vehicle Specifirations.

Wheelbase

Length, over-all
Width, over-all
Height, over-all-top up

-top down 52 in.

Wheel size combat 16 x 4.50 E

Tire size
Tire pressure (front and rear)
Tire type
Tire plies
Tread (center-to-center)-front

-rear

Crew, operating

Passenger capacity including crew

10

.., 62 in.

16 x 6.00 in.

mud and snow

80 in.

1321/d in.

69$/4 in.

35 lb

6

49 in.

49 in.

2

5

TM 9-803

DESCRIPTION AND TABULATED DATA

Weights:

Road, including gas and water 2,453 lb
Gross (loaded) 3,253 lb
Shipping (less water and fuel) 2,337 lb
Boxed gross 3,062 lb
Maximum pay load 800 lb
Maximum trailed load 1,000 lb
Ground clearance 8¾ in.
Pintle height (loaded) 21 in.

Kind and grade of fuel (octane rating) Gasoline (68 mm)

Approach angle 45 deg
Departure angle 35 deg
Shipping dimensions—cubic feet 331

—square feet 57

b. Performance.

Maximum allowable speeds (mph) with transfer case in “HIGH” range:

High gear (3rd) 65

Intermediate gear (2nd) 41
Low gear (1st) 24
Reverse gear . 18
Maximum allowable speeds (mph) with transfer case in
“LOW” range:
High gear (3rd) 33
Intermediate gear (2nd) 21
Low gear (1st) 12
Reverse gear 9
Maximum grade ability 60 pct
Minimum turning radius—right 17½ ft
—left 171/2 ft
Maximum fording depth. 21 in.
Towing facilities—front none
—rear pintle hook
Maximum draw-bar pull 1,930 lb
Engine idle speed 600 rpm
Miles per gallon—(high gear—high range)
average conditions 20
Cruising range—(miles) average conditions 20

3

c. Capacities.

Engine crankcase capacity—dry 5 qt

—refill 4 qt

Transmission capacity % qt

Transfer case capacity 1 I/I qt

11

TM 9-803

3

+TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

Front axle capacity (differential) . 1y4 qt
Rear axle capacity (differential) 1r/4 qt

Front axle steering knuckle universal joint. j/4 qt
Steering gear housing y4 qt
Air cleaner (oil bath). . s/s qt

Fuel tank capacity 15 gal

Cooling system capacity 11 qt
Brake system (hydraulic brake fluid) j/4 qt
Shock absorbers--front 5 oz

-rear .., . __.. 53/4 02

d. Communications.

(1) RADIO OUTLET Box. A radio outlet box is provided on the
later vehicles to use the vehicle battery (6-volt current supply). This
outlet is located against the body side panel at the right front seat.

(2) AUXILIARY GENERATOR. A 12-volt, 55ampere auxiliary gen­erator is furnished on some vehicles. The generator is driven by a
V-belt from a power take-off unit on the rear of the transfer case.
Instructions for operation and care accompany those vehicles.

12

TM 9-803

4

Section III

DRIVING CONTROLS AND OPERATION

Paragraph

Instruments and controls . . , . .
Use of instruments and controls in vehicular operation. . .

Towing the vehicle....................................... 6

A B C

4

5

WVUTSRQPON

A

STEERING WHEEL

E

HORN BUTTON

WINDSHIELD WIPERS

C

D

WINDSHIELD ADJUSTING ARMS

E

AMMETER

F

HAND BRAKE

G

WINDSHIELD CLAMPS

H

CAUTION PLATE

I

NAME PLATE

J

SHIFT PLATE

K

TRANSMISSION GEAR SHIFT LEVER

1

TRANSFER CASE SHIFT LEVER-FRONT AXLE DRIVE AC

M

TRANSFER CASE SHIFT LEVER-AUXILIARY RANGE

N

STARTING SWITCH

0

TEMPERATURE GAGE
ACCELERATOR FOOT REST

;

SPEEDOMETER

ML

R

ACCELERATOR (FOOT THROTTLE)

S

OIL PRESSURE GAGE

1

FUEL GAGE

U

BRAKE PEDAL

V

INSTRUMENT PANEL LIGHT SWITCH

W

CLUTCH PEDAL

X

FUEL TANK

Y

FIRE EXTINGUISHER

Z

SAFETY STRAP

AA

HEADLIGHT FOOT SWITCH (BEAM CONTROL)

AR

BLACKOUT LIGHT SWITCH
BLACKOUT DRIVING LIGHT SWITCH
REAR VISION MIRROR

AD

AE

CHOKE CONTROL

AF

IGNITION SWITCH

AC

HAND THROTTLE

AH

RIFLE HOLDER

K J I

RA PD 334753

Figure 5-Instruments and Controls

INSTRUMENTS AND CONTROLS.

4.

a. Instruments.

(1) AMMETER (fig. 5). The ammeter on the instrument panel
indicates the rate of current flow when the generator is charging the
battery, and also indicates the amount of current being consumed
when the engine is idle.

(2) FUEL GAGE (fig. 5). The fuel gage on the instrument panel

13

TM 9-803

4

‘/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

Figure 6-Name Pfafe

RA PD 305162

Figure 7-Caution Plate

RA PD 330838

RA PD 305161

Figure (I-Shift Plate

14

TM 9-803

4

DRIVING CONTROLS AND OPERATION

is an electrical unit which indicates the fuel level in the tank, and
only registers while the ignition switch is turned on.

(3) OIL PRESSURE GAGE (fig. 5). The oil pressure gage located
on the instrument panel indicates the oil pressure when the engine
is running.

(4) SPEEDOMETER (fig. 5). The speedometer on the instrument
panel indicates in miles per hour the speed at which the vehicle is
being driven. The odometer (in upper part of speedometer face)
registers the total number of miles the vehicle has been driven. A
trip indicator (in lower part of speedometer face) gives distance
covered on any trip. Set trip indicator by turning the knurled con­trol shaft extending through back of the speedometer.

the temperature of the solution in the cooling system.

driving light switch (B.O. DRIVE) on the instrument panel controls
the blackout driving light located on the left front fender, to furnish
additional light during blackout periods. To operate light, first pull
the blackout light switch button to the first position, then pull black­out driving light switch knob. To switch off the light, push in black­out drivind light switch knob.

TEMPERATURE GAGE (fig. 5). The temperature gage registers

(5)

b. Controls.

(1) BLACKOUT DRIVING LIGHT SWITCH (fig. 5). The blackout

Fieure 9-Blackout Light Switch Operating ?ositions

(2) BLACKOUT LIGHT SWITCH (fig. 5). The knob on the instru­ment panel (LIGHTS) controls the entire lighting system, including
the instrument panel lights, blackout driving light, and stop lights.
A circuit-breaker type fuse, on the back of the switch, opens when

a short circuit occurs, and closes when the thermostatic element cools.
The light switch is a four-position push-pull type with a safety lock

(fig. 9). When the control knob is pulled out to the first position, the

blackout headlights and blackout stop and taillights are turned on.

15

TM 9-803

4

I/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

The switch control knob travel is automatically locked in this position
by the lock-out button to prevent accidentally turning on of the
service (bright) lights in a blackout area. To obtain service lights,
push in on lock-out control button on the left side of the switch, and
pull out control knob to second position. When switch is in this posi­tion service headlights, service stop and taillights are turned on, and
the panel lights can be turned on by pulling out on the knob

(PANEL LIGHTS). CAUTION: When driving during the day, press

in lock-out control button, and pull control knob out to the last or

stop light position to cause only the regular stop light to function.

and FORD MODEL GPW)

Figure IO- Generator Brace

RA PD 305165

(3) PANEL LIGHT SWITCH (fig. 5). The panel light switch knob

(PANEL LIGHTS), located on the instrument panel, controls the

lights to illuminate the panel instruments and controls. The blackout
light switch (subpar. b (2) above) must be in service (bright light)
position for this switch to control the panel lights.

(4) FIRE EXTINGUISHER (fig. 5). The fire extinguisher is mounted
inside the left cowl panel. To remove, pull outward on the clamp
release lever. To operate extinguisher, hold body in one hand and
with the other, turn handle to left one-quarter turn, which releases
plunger lock. Use pumping action to force liquid on base of fire. Read
instructions on fire extinguisher plate.

16

TM 9-803

4-5

DRIVING CONTROLS AND OPERATION

(5)

HAND BRAKE (fig. 5). The hand brake is applied by pulling

out on the handle at the center of the instrument panel. Pull the

handle out in a vertical position when the vehicle is parked. The
brake is released by turning the handle one-quarter turn.

(6) WINDSHIELD ADJUSTING ARMS (fig. 5). The windshield
adjustment arms are mounted on each end of the windshield frame.
To open windshield, loosen knobs and push forward on lower part,
then set by tightening the knobs.

(7) WINDSHIELD CLAMPS (fig. 5). The windshield clamps are
located on the lower part of the windshield. Pull up on both clamps

and unhook them, after which the windshield can be lowered on top
of the hood. Be sure to hook down the windshield, using the hold-

down catches on both sides of the hood.

(8) GENERATOR BRACE (fig. 10). The generator brace can be
pulled up to release tension on the fan belt and stop the fan from
throwing water over the engine when crossing a stream. Pull gen-

erator out to running position as soon as possible thereafter, and it
will lock in place. CAUTION: Be sure fan belt is on pulleys.

(9)

OTHER INSTRUMENTS AND CONTROLS. Other instruments and

controls are of the conventional type, and are shown in figure 5.

5. USE OF INSTRUMENTS AND CONTROLS IN VEHICULAR

OPERATION.

a. Before-operation Service. Perform the services in paragraph

13 before attempting to start the engine.

b.

Starting Engine. To start the engine proceed as follows:

(1)

Put transmission gearshift lever in neutral position (fig. 8).

(2)

Pull out hand throttle button about 3/4 inch to 1 inch.

(3) Pull out choke button all the way. NOTE: Ch’oking is not

necessary when engine is warm.

(4)

Turn ignition to “ON” position.

(5) Depress clutch pedal to disengage clutch, and hold pedal

down while engine is started.

(6) Step on starting switch to crank again. Release switch as

soon as engine starts.

(7) Adjust choke and throttle control buttons to obtain proper

idling speed. As engine warms up, push choke button all the way in.

(8)

Check oil pressure gage reading; at idle speed the indicator

hand should show at least 10 on the gage.

(9) Check ammeter for charge reading. Check fuel gage for

indication of fuel supply.

(10)

After engine has operated a few minutes, check temperature
gage reading. Normal operating temperature is between 160°F and
185OF.

(11)

In extremely cold weather refer to paragraph 7.

c. Placing Vehicle in Motion.

(1)

For daytime driving turn on service stop light (par. 4 b (2)).

(2) Place transfer case right-hand shift lever in rear position to

soX!ri 0---48~~-2

17

TM 9-803

5

I/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

engage “HIGH” range, then place center shift lever in forward posi­tion to disengage front axle (fig. 8).

(3) Depress clutch pedal, and move transmission shift lever

toward driver and backward to engage low (1st) gear (fig. 8).

(4) Release parking (hand) brake.

(5) Slightly depress accelerator to increase engine speed, and at
the same time slowly release clutch pedal, increasing pressure on
accelerator as clutch engages and vehicle starts to move. NOTE:

During the following operations perform procedures outlined in para­graph 14.

(6) Increase speed to approximately 10 miles per hour, depress

clutch pedal, and at the same time release pressure on accelerator.
Move transmission shift lever out of low gear into neutral, and then
into second gear. No double clutching is required. Release clutch
pedal and accelerate engine.

(7) After vehicle has attained a speed of approximately 20 miles

per hour, follow the same procedure as outlined above in order to

shift into high (3rd) gear, moving the gearshift lever straight back.

d. Shifting to Lower Gears in Transmission. Shift to a lower
gear before engine begins to labor, as follows: Depress clutch pedal
quickly, shift to next lower gear, increase engine speed, release clutch
pedal slowly, and accelerate. When shifting to a lower gear at any
rate of vehicle speed, make sure that the engine speed is synchronized
with vehicle speed before clutch is engaged.

e. Shifting Gears in Transfer Case (fig. 8). The transfer case is
the means by which power is applied to the front and rear axles. In
addition, the low gear provided by the transfer case further increases
the number of speeds provided by the transmission. The selection of
gear ratios depends upon the road and load conditions. Shift gears

in the transfer case in accordance with the shift plate (fig. S), and
observe the instructions on the caution plate (fig. 7). The transmis-

sion gearshift does not in any way affect the selection or shifting of
the transfer case gears. Vehicle may be driven by rear axle, or by both

front and rear axles. The front axle cannot be driven independently.

(1) FRONT AXLE ENGAGEMENT. Front axle should be engaged

only in off-the-road operation, slippery roads, steep grades, or during

hard pulling. Disengage front axle when operating on average roads
under normal conditions.

(a) En&aging Front Axle with Transfer Case in “HIGH” Range.
With transfer case in “HIGH” range, move front axle drive shift lever

to “IN” position. Depressing the clutch pedal will facilitate shifting.

(b) Disengaging Front Axle with Transfer Case in “HIGH”

Range. Move front axle drive shift lever to “OUT” position. Depress

the clutch pedal to facilitate shifting.

(c) Disengaging Front Axle when Transfer Case is in “LOW.”

1. Depress clutch pedal, then shift transfer case lever into

“HIGH.”

2. Shift front axle drive lever into “OUT” position.
18

TM 9-803

5-6

DRIVING CONTROLS AND OPERATION

3. Release clutch pedal and accelerate engine to desired speed.

(2) ENGAGING TRANSFER CASE LOW RANGE. Transfer case LOW

range cannot be engaged until front axle drive is engaged.

(a) Engage front axle drive (subpar. e (1) above).
(b) Depress clutch pedal and move transfer case shift lever into

“IV (neutral) position.

Ro1s.c.~~ rltrtrh nm-lal anA nrrrlr=cate ena;ne

(c)

*.bAc”“.. L.YCC.. y-‘Cuu _...A Y..LL.L.“... . . ..b...L.

(d) Depress clutch pedal again and move transfer case shift lever

forward into “LOW” position.

(e> Release clutch pedal, and accelerate engine to desired speed.

(3) ENGAGING TRANSFER CASE-“LOW” to “HIGH.” This shift

can be made regardless of vehicle speed.

(a) Depress clutch pedal and move transfer case shift lever into

“HIGH” position.

(b) Release clutch pedal, and accelerate engine to desired speed.

f: Stopping the Vehicle.

apply brakes by depressing brake pedal.

(1) When vehicle speed has been reduced to engine idle speed,

depress clutch pedal and move transmission shift lever to “N”

(neutral) position (fig. 8).

(2) When vehicle has come to a complete stop, apply parking

(hand) brake, and release clutch and brake pedals.

g. Reversing the Vehicle. To shift into reverse speed, first bring

the vehicle to a complete stop.

(1) Depress clutch pedal.

(2) Move transmission shift lever to the left and forward into

“R” (reverse) position.

(3) Release clutch pedal slowly. and accelerate as load is picked

up.

h. Stopping the Engine. To stop the engine turn the ignition

switch to “OFF” position. NOTE: Before a new or reconditioned

vehicle is first put into service: make run-in tests as outlined in sec­tion 10.

Remove foot from accelerator, and

6. TOWING THE VEHICLE.

a. Attaching Tow Line. To tow vehicle attach the chain, rope or

cable to the front bumper bar at the frame side rail gusset (fig. 11).

Do not tow from the middle of the bumper. To attach tow line, loop
chain, rope, or cable over top of bumper, bring tow line up across
front of bumper, and back on opposite side of frame, then hook or tie.

h. Towing to Start Vehicle. Place transfer case (aux. RANGE)

.h;ff la.,-v nf tn....4 . ..ah.rl, en l ha ram.. I“UTr,U”\ D1ms.a f-n-+ owla

L.IIIC SL”LA “I CVWL” “LlA,C.x. L” CA.C ‘La, \ AAIU11 ,.

1 AcIbC AI”“C a.%‘&

drive shift lever in “OUT” (forward) position. Depress clutch pedal

and engage transmission in high (3rd) speed. Switch ignition “ON,”
pull out choke control knob (if engine is cold), pull out throttle knob
about 1 inch, release parking (hand) brake, and tow vehicle. After

19

TM 9-803

6

l/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

vehicle is under way, release clutch pedal slowly. As engine starts,
regulate choke and throttle controls and disengage clutch, being
careful to avoid overrunning towing vehicle or tow line.

c. Towing Disabled Vehicle. When towing a disabled vehicle

exercise care so that no additional damage will occur.

fer case into neutral position and follow steps (c) and (d) below.

at the front and rear axles by removing the universal joint U-bolts,
being careful not to lose the bearing races and rollers. Securely fasten
the shafts to the frame with wire or remove dust cap and pull apart
at the universal joint splines. Place bolts, nuts, rollers, and races in
the glove compartment.

A. I XX,rrX7?7. n _\I P_-r,rrr7r\

(1)

X7L.L. ““~l?rc.L3 “IY UK”“IY”.

(a) If transfer case is not damaged, shift transmission and trans-

(b) If transfer case is damaged, disconnect both propeller shafts

(c) If the front axle differential or propeller shaft is damaged,

remove front axle shaft driving flanges. Place front axle drive shift

lever in “OUT” (forward) position and drive vehicle under own
power.

(d) If the rear axle differential is damaged, remove the rear axle
shafts; remove rear propeller shaft at rear universal joint U-bolts and
front universal joint snap rings in forward flange, then drive out
bearing cups. Place front axle drive shift lever in “IN” (rear) position
and this will allow front axle drive to propel vehicle under own
power.

(e) If rear propeller shaft only is damaged, remove as described

in step (d) above.

(2) TOWING VEHICLE WITH FRONT OR REAR WHEELS OFF

GROUND. If vehicle is to be towed in this manner be sure that transfer
case shift lever is placed in “N” (neutral) position and front axle

drive shift lever is placed in “OUT” (disengaged) position.

20

TM 9-803

7

Section IV

OPERATION UNDER UNUSUAL CONDITIONS

Paragraph

Operation in cold weather
Operation in hot weather
Operation in sand ,.
Operation in ianding
Decontamination

7. OPERATION IN COLD WEATHER.
a. Purpose. Operation of automotive equipment at subzero

temperatures presents problems that demand special precautions and
extra careful servicing from both operation and maintenance person­nel, if poor performance and total functional failure are to be avoided.

b. Gasoline. Winter grade of gasoline is designed to reduce cold

. .._-&I___. ^L_._L:-- -1:cf-..Ic:,.-.

wcaL,lrl YLill L111g UIIIICUILICS,
should be used in cold weather operation.

c. Storage and Handing of Gasoline. Due to condensation of

moisture from the air, water will accumulate in tanks, drums, and

containers. At low temperatures, this water will form ice crystals that

will clog fuel lines and carburetor jets, unless the following precau-

tions are taken:

(1) Strain the fuel through filter paper, or any other type of

strainer that will prevent the passage of water. CAUTION: Gasoline

flowing over a surface generates static electricity that wiN result in a
spark, unless means are provided to ground the electricity. Always
provide a metallic contact between the container and the tank, to

assure an effective ground.

(2) Keep tank full, if possible. The more fuel there is in the tank,

the smaller will be the volume of air from which moisture can be

condensed.

(3) Add ‘/z pint of denatured alcohol, Grade 3, to the fuel tank

each time it is filled. This will reduce the hazard of ice formation in

the fuel.

(4) Be sure that all containers are thoroughly clean and free from

rust before storing fuel in them.

(5) If possible, after filling or moving a container, allow the fuel

to settle before filling fuel tank from it.

(6) Keep all closures of containers tight to prevent snow, ice, dirt,

and other foreign matter from entering.

(7) Wipe all snow or ice from dispensing equipment and from

around fuel tank filler cap before removing cap to refuel vehicle.

d. Lubrication.

(1) TRANSMISSION AND DIFFERENTIAL.

tbleiefoie 4.l_ . . ..-c_- --_.l- __^L^^ c..,.,

, L‘lC Wl‘lLCl g;lauc lll”L”‘ ,UCl

21

7

8

9
i0
11

TM 9-803

7

I/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

(a) Universal gear lubricant, SAE 80, where specified on figure 14,

is suitable for use at temperatures as low as -20°F. If consistent
temperature below O’F is anticipated, drain the gear cases while
warm, and refill with Grade 75 universal gear lubricant, which is suit­able for operation at all temperatures below +32’F. If Grade 75
universal gear lubricant is not available, SAE 80 universal gear lubri­cant diluted with the fuel used by the engine, in the proportion of one
part fuel to six parts universal gear lubricant, may be used. Dilute
make-up oil in the same proportion before it is added to gear cases.

(b) After engine has been warmed up, engage clutch, and main­tain engine speed at fast idle for 5 minutes, or until gears can be
engaged. Put transmission in low (first) gear, and drive vehicle for

100 yards, being careful not to stall engine. This will heat gear lubri-

cants to the point where normal operation can be expected.

(2) CHASSIS POINTS. Lubricate chassis points with general

purpose grease, No. 0.

(3) STEERING GEAR HOUSING. Drain housing, if possible, or use

suction gun to remove as much lubricant as possible. Refill with uni­versal gear lubricant, Grade 75, or, if not available, SAE 80 universal
gear lubricant diluted with fuel used in the engine, in the proportion
of one part fuel to six parts SAE 80 universal gear lubricant. Dilute
make-up oil in the same proportion before it is added to the housing.

(4) OILCAN POINTS. For oilcan points where engine oil is pre-

scribed for above O°F, use light lubricating, preservative oil.

e. Protection of Cooling Systems.

(1) USE ANTIFREEZE COMPOUND. Protect the system with anti-

freeze compound (ethylene-glycol type) for operation below i 32’F.
The following instructions apply to use of new antifreeze compound.

(2) CLEAN COOLING SYSTEM. Before adding antifreeze compound,

clean the cooling system, and completely free it from rust. If the cool-

ing system has been cleaned recently, it may be necessary only to

drain, refill with clean water, and again drain. Otherwise the system
should be cleaned with cleaning compound.

(3) REPAIR LEAKS. Inspect all hoses, and replace if deteriorated.
Inspect all hose clamps, plugs, and pet cocks and tighten if necessary.
Repair all radiator leaks before adding antifreeze compound. Correct
all leakage of exhaust gas or air into the cooling system.

(4) ADD ANTIFREEZE COMPOUND. When the cooling system is
clean and tight, fill the system with water to about one-third capacity.
Then add antifreeze compound, using the proportion of antifreeze

compound to the cooling system capacity indicated below. Protect
the system to at least lOoF below the lowest temperature expected to

be experienced during the winter season.

22

TM 9-803

7

OPERATION UNDER UNUSUAL CONDITIONS

ANTIFREEZE COMPOUND CHART

(for 11 -quart capacity cooling system)

Tsmperatur*

+lO°F .,.,.. ._._........_._

O°F 33/4 qt

- 10°F

--20°F 43/4 qt

-30°F ._.... _. _. 5% qt

-40°F. ._.........._

(5) WARM THE ENGINE. After adding antifreeze compound, fill

with water to slightly below the filler neck: then start and warm the
engine to normal operating temperature.

(6) TEST STRENGTH OF SOLUTION. Stop the engine and check the

solution with a hydrometer, adding antifreeze compound if required.

TwcDFrr Wurzu1”

(7)

IL..,1 x,L L . . YYLX” 1 . &&I YCI . AL._,

ln .ZPPII;FP ;nrner+ the mnlant w~~lrl,, mr

strength and color. If rusty, drain and clean cooling system thor­oughly, and add new solution of the required strength.

(8) CAUTIONS.

(a) Antifreeze compound is the only antifreeze material author-

ized for ordnance materiel.

(b) It is essential that antifreeze solutions be kept clean. Use only

containers and water that are free from dirt, rust, and oil.

(c) Use an accurate hydrometer. To test a hydrometer, use one
part antifreeze compound to two parts water. This solution will pro­duce a hydrometer reading of O°F.

(d) Do not spill antifreeze compound on painted surfaces.

f. Elettrical Systems.

(1) GENERATOR AND CRANKING MOTOR. Check the brushes,
commutators, and bearings. See that the commutators are clean. The
large surges of current which occur when starting a cold engine
require good contact between brushes and commutators.

(2) WIRING. Check, clean, and tighten all connections, especially
the battery terminals. Care should be taken that no short circuits are
present.

(3) COIL. Check coil for proper functioning by noting quality of
spark.

(4) DISTRIBUTOR. Clean thoroughly, and clean or replace points.

Check the points frequently. In cold weather, slightly pitted points
may prevent engine from starting.

(5) SPARK PLUGS. Clean and adjust or replace, if necessary. Tf it

is difficult to make the engine fire, reduce the gap to 0.005 inch less

than that recommended for normal operation (par. 67 1)). This will

make ignition more effective at reduced voltages likely to prevail.

23

Antifreeze Compound
(ethylene-glycol type)

3 qt

4% nt

‘,ri -I-

6 qt

‘a’YyLC._ L&1.. ~vvIcIssc ..LC...J

TM 9-803

7

I/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

(6) TIMING. Check carefully. Care should be taken that the spark

is not unduly advanced nor retarded.

(7) BATTERY.

(a) The efficiency of batteries decreases sharply with decreasing

temperatures, and becomes practically nil at -4O’F. Do not try to
start the engine with the battery when it has been chilled to tem­peratures below -30°F until battery has been heated, unless a warm
slave battery is available. See that the battery is always fully

charged, with the hydrometer reading between 1.275 and 1.300. A

fully charged battery will not freeze at temperatures likely to be

encountered even in arctic climates, but a fully discharged battery

will freeze and rupture at +5’F.

(b) Do not add water to a battery when it has been exposed to

subzero temperatures unless the battery is to be charged immediately.

If water is added and the battery not put on charge, the layer of water
will stay at the top and freeze before it has a chance to mix with
the acid.

(8) LIGHTS. Inspect the lights carefully. Check for short circuits

and presence of moisture around sockets.

(9) ICE. Before every start, see that the spark plugs, wiring, or

other electrical equipment is free from ice.

g. Starting and Operating Engine.

(1) INSPECT CRANKING MOTOR MECHANISM. Be sure that no
heavy grease or dirt has been left on the cranking motor throwout
mechanism. Heavy grease or dirt is liable to keep the gears from being

meshed, or cause them to remain in mesh after the engine starts run­ning. The latter will ruin the cranking motor and necessitate repairs.

(2) USE OF CHOKE. A full choke is necessary to secure the rich
air-fuel mixture required for cold weather starting. Check the butter-

fly valve to see that it closes all the way, and otherwise functions
properly.

(3) CARBURETOR AND FUEL PUMP. The carburetor, which will
give no appreciable trouble at normal temperatures, is liable not to
operate satisfactorily at low temperatures. Be sure the fuel pump has
no leaky valves or diaphragm, as this will prevent the fuel pump from

delivering the amount of fuel required to start the engine at low
temperatures, when turning speeds are reduced to 30 to 60 revolu­tions per minute.

(4) AIR CLEANERS. At temperatures below O°F do not use oil in

air cleaners. The oil will congeal and prevent the easy flow of air.

Wash screens in dry-cleaning solvent, dry, and replace. Ice and frost
formations on the air cleaner screens can cause an abnormally high

intake vacuum in the carburetor air horn hose, resulting in collapse.

(5) FUEL SYSTEM. Remove and clean sediment bulb, strainers,

etc., daily. Also drain fuel tank sump daily to remove water and dirt.

24

OPERATION UNDER UNUSUAL CONDITIONS

(6)

STARTING THE ENGINE. Observe the following precautions in

addition to the normal starting procedure (par. 5 a and b).

Clean ignition wires and outside of spark plugs of dirt and

(4

frost.

Free distributor point arm on post and clean points.

(h)

Be sure carburetor choke closes fully.

(c)

Operate fuel pump hand lever to fill carburetor bowl (fig.

(d)

12).
Free up engine with hand crank or use slave battery.

(e)

Stop engine if no oil pressure shows on gage.

ffl

TM 9-803

7

Figure I2-Fuel Pump, Hand Operation

(g)

Engage clutch to warm up transmission oil before attempting

to move vehicle.

(h)

Check engine operation for proper condition (par. 13 b (22)).

h. Chassis.

(1) BRAKE BANDS. Brake bands, particularly on new vehicles,

have a tendency to bind when they are very cold. Always have a

blowtorch handy to warm up these parts, if they bind prior to mov­ing, or attempting to move, the vehicle. Parking the vehicle with the
brake released will eliminate most of the binding. Precaution must be

taken, under these circumstances, to block the wheels or otherwise

prevent movement of the vehicle.

25

TM 9-803

7-9

l/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

(2) EFFECT OF Low TEMPERATURES ON METALS. Inspect the

vehicle frequently. Shock resistance of metals, or resistance against

breaking, is greatly reduced at extremely low temperatures. Operation
of vehicles on hard, frozen ground causes strain and jolting which will
result in screws breaking, or nuts jarring loose.

(3) SPEEDOMETER CABLE. Disconnect the oil-lubricated speed-

ometer cable at the drive end when operating the vehicle at tempera-

tures of -30°F and below. The cable will often fail to work properly

at these temperatures, and sometimes will break, due to the excessive
drag caused by the high viscosity of the oil with which it is lubricated.

8. OPERATION IN HOT WEATHER.

a. Protection of Vehicle. In extremely hot weather avoid the

continuous use of low gear ratios whenever possible. Check and
replenish oil and water frequently. If a flooded condition of the
engine is experienced in starting, pull the throttle control out, push

choke control in, and use the cranking motor. When engine starts,
adjust throttle control.

(1) COOLING SYSTEM. Rust formation occurs more rapidly dur-

ing.high temperatures; therefore, add rust preventive solution to the

cooling system, or clean and flush the system at frequent intervals.

(2) LUBRICATION. Lubricate the vehicle for hot weather operation

(par. 8).

(3) ELECTRICAL SYSTEM. Check the battery solution level fre­quently during hot weather operation, and add water as required to
keep it above the top of the plates. If hard starting is experienced in
hot, damp weather or quick changes in temperature, dry the spark

plugs, wires, and both inside and outside of distributor cap.

9. OPERATION IN SAND.

a. Operation. Reduce tire pressures in desert terrain if character

of sand demands this precaution. When operating in sand deep

enough to cause the use of a lower gear, do not exceed the speed
specified on the caution plate for the particular gear ratio (fig. 7).

b. Starting the Vehicle. When starting the vehicle in sand,

gravel, or soft terrain, engage the front wheel drive (par. 5 e (1)).

Release clutch pedal slowly so the wheels will not spin and “dig in,”
necessitating a tow or “winch-out.”

c. Clutch. Do not attempt to “jump” or “rock” the vehicle out

with a quick engagement of the clutch, particularly if a tow or winch

is available. Racing the engine usually causes the wheels to “dig in”
farther.

d. Air Cleaner. In sandy territory clean the carburetor air cleaner

more often. The frequency of cleaning depends upon the severity of

the sandy condition.

26

TM 9-803

9-11

OPERATION UNDER UNUSUAL CONDITIONS

e.

Radiator. In desert operation check the radiator coolant supply

frequently, and see that the air passages of the core do not become

clogged.

f. For additional information on technique of operating the

vehicle in sand, refer to FM 31-25.

10. OPERATION IN LANDING.

a. Inspection. As soon as possible after completing a landing or

operation in water, inspect the vehicle for water in the various units.

(1) ENGINE. Drain the engine crankcase oil. If water or sludge
is found, flush the engine, using a mixture of half engine oil SAE 10
and half kerosene. Before putting in new oil, clean the valve chamber,
drain and clean the oil filter, and install a new filter element.

(2) FUEL SYSTEM. Inspect the carburetor bowl, fuel strainers,
fuel pump, filter, fuel tank, and lines. Clean the air cleaner and
change the oil.

(3) POWER TRAIN. Inspect the front and rear axle housings,
wheel bearings, transmission, and transfer case lubricant for presence
of sludge. If sludge is found, renew the lubricant after cleaning the

units with a mixture of half engine oil SAE 10 and half kerosene.
Lubricate the propeller shaft universal joints and spring shackles to

force out any water which might damage parts.

11. DECONTAMINATION.

a. Protection. For protective measures against chemical attacks

and decontamination refer to FM 17-59.

27

TM 9-803

12

‘/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

Section V

FIRST ECHELON PREVENTIVE MAINTENANCE SERVICE

Paragraph

Purpose ................................................ 12

Before-operation service ..................................

During-operation service ............................... 14

At-halt service ........................................ 15

After-operation and weekly service ........................ 16

12. PURPOSE.

a. To ensure mechanical efficiency it is necessary that the vehicle

be systematically inspected at intervals each day it is operated, also
weekly, so that defects may be discovered and corrected before they
result in serious damage or failure. Certain scheduled maintenance
services will be performed at these designated intervals. The services

set forth in this section are those performed by driver or crew before
operation, during operation, at halt, and after operation and weekly.

b. Driver preventive maintenance services are listed on the back

“Driver’s Trip Ticket and Preventive Maintenance Service

of

Record,” W.D. Form No. 48, to cover vehicles of all types and models.
Items peculiar to specific vehicles, but not listed on W.D. Form No.
48, are covered in manual procedures under the items to which they

are related. Certain items listed on the form that do not pertain to
the vehicle involved are eliminated from the procedures as written
into the manual. Every organization must thoroughly school each

driver in performing the maintenance procedures set forth in manuals,

whether they are listed specifically on W.D. Form No. 48 or not.

c. The items listed on W.D. Form No. 48 that apply to this
vehicle are expanded in this manual to provide specific procedures
for accomplishment of the inspections and services. These services

rr +r\

fnAl;tatn ;e.nnort;r\.. c.nA P.T~~P.-..P the t;mo nf the

are arrange-

C” IEIs,LA‘L~CL ,lK?p~L._L”rr alIll ..“1*.TLl SL LllC CllllC “1 L&I..

driver, and are not necessarily in the same numerical order as shown
on W.D. Form No. 48. The item numbers, however, are identical with
those shown on that form.

d. The general inspection of each item applies also to any sup-

porting member or connection, and generally includes a check to see
whether the item is in good condition, correctly assembled, secure,
or excessively worn.

(1) 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: not bent or twisted, not chafed or burned,
not broken or cracked, not bare or frayed, not dented or collapsed,
not torn or cut.

28

i3

TM 9-803

12-13

FIRST ECHELON PREVENTIVE MAINTENANCE SERVICE

(2) The inspection of a unit to see that it is “correctly assembled”

is usually an external visual inspection to see whether or not it is in

its normal assembled position in the vehicle.

(3) The inspection of a unit to determine if it is “secure” is
usually an external visual examination, a hand-feel, wrench, or pry­bar check for looseness. Such an inspection should include any

brackets, lock washers, lock nuts, locking wires, or cotter pins used
in assembly.

“Excessively worn” will be understood to mean worn, close

(4)

to or beyond, serviceable limits, and likely to result in failure if not

replaced before the next scheduled inspection.

e. Any defects or unsatisfactory operating characteristics beyond
the scope of the first echelon to correct must be reported at the
earliest opportunity to the designated individual in authority.

13. BEFORE-OPERATION SERVICE.

a. This inspection schedule is designed primarily as a check to

see that the vehicle has not been tampered with or sabotaged since

the After-operation Service was performed. Various combat condi­tions may have rendered the vehicle unsafe for operation, and it is
the duty of the driver to determine whether or not the vehicle is in
condition to carry out any mission to which it is assigned. This
operation will not be entirely omitted, even in extreme tactical

situations.

b. Procedures. Before-operation Service consists of inspecting

items listed below according to the procedure described, 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 AND DAMAGE. Examine exterior of

vehicle, engine, wheels, brakes, and steering control for damage by

falling debris, shell fire, sabotage, or collision. If wet, dry the ignition

parts to ensure easy starting.

(2) ITEM 2, FIRE EXTINGUISHER. Be sure fire extinguisher is full,

nozzle is clean, and mountings secure.

(3) ITEM 3, FUEL, OIL, AND WATER. Check fuel tank, crankcase,
and radiator for leaks or tampering. Add fuel, oil, or water as
needed. Have value of antifreeze checked. If, during period when
antifreeze is used, it becomes necessary to replenish a considerable
amount of water, report unusual losses.

(4) ITEM 4, ACCESSORIES AND DRIVES. Inspect carburetor, gener­ator, regulator, cranking motor, and water pump for loose connec­tions and security of mountings. Inspect carburetor and water pump
for leaks.

(5) ITEM 6, LEAKS, GENERAL. Look on ground under vehicle for
indications of fuel, oil, water, brake fluid, or gear oil leaks. Trace

leaks to source, and correct or report to higher authority.

29

TM 9-803

13

r/,-TON 4 x 4 TRUCK (WILLYS-OVERLAND MODEL MB

and FORD MODEL GPW)

(6) ITEM 7, ENGINE WARM-UP. Start engine, observe cranking

motor action, listen for unusual noise, and note cranking speed. Idle

engine only fast enough to run smoothly. Proceed immediately with

following services while engine is warming up.

(7) ITEM 8, CHOKE. As engine warms, push in choke as required

for smooth operation, and to prevent oil dilution.

(8) ITEM 9, INSTRUMENTS.

(a) Fuel Gage. Fuel gage should indicate approximate amount

of fuel in tank.

(6) Oil Pressure Gage. Normal oil pressure should not be below

10 with engine idling, and should range from 40 to 50 at running

speeds (at normal operating temperature). If gage fails to register

within 30 seconds, stop engine,
authority.

(c) Temperature Indicator. Temperature should rise slowly dur-

ing warm-up. Normal operating temperature range is 160°F to 185’F.

(d) Ammeter. Ammeter should show high charge for short period

after starting and positive (plus) reading above 12 to 15 miles per

hour with lights and accessories off. Zero reading is normal with

lights and accessories on.

(9) ITEM 10, HORN AND WINDSHIELD WIPERS. Sound horn, tacti­cal situation permitting, for proper operation and tone. Check both
wipers for secure attachment and normal full contact operation

through full stroke.

(10) ITEM 11, GLASS AND REAR VIEW MIRROR. Clean windshield

and rear view mirror and inspect for cracked, discolored, or broken

glass. Adjust mirror.

(11) ITEM 12, LIGHTS AND REFLECTORS. Try switches in each

position and see if lights respond. Lights and warning reflectors must

be securely mounted, clean, and in good condition. Test foot control

of headlight beams.

(12) ITEM 13, WHEEL AND FLANGE NUTS. Observe whether or not

all wheel and flange nuts are present and tight.

(13) ITEM 14, TIRES. If time permits, test tires with gage, includ­ing spare; normal pressure is 35 pounds with tires cold. Inspect tread
and carcass for cuts and bruises. Remove imbedded objects from

treads.

(14) ITEM 15, SPRINGS AND SUSPENSION. Inspect springs for

sagged or broken leaves, shifted leaves, and loose or missing rebound

clips.

(15) ITEM 16, STEERING LINKAGE. Examine steering gear case,

connecting links, and Pitman arm for security and good condition.

Test steering adjustment, and free motion of steering wheel.

(16) ITEM 17, FENDERS AND BUMPERS, Examine fenders and

bumpers for secure mounting and serviceable condition.

and correct or report to higher

30