STEERING SYSTEM ADJUSTMENT - continued - TM-10-3930-647-14-P0103

16. Now check for free play caused by loose

hand wheel until pressure drops to a minimum:

or misadjusted linkage. T O d o t h i s . . . f i r s t ,

Hydracool 90 PSI and Hydratork 70 PSI.

torque the cylinder valve control ball stud nut

(L) to 90 to 110 pound feet. Then...check the

24. When minimum pressure is reached,

cylinder valve control stud (M) for movement

hold the hand wheel at this position and screw

before the steer wheels move.

Its normal allow-

in the pitman arm adjusting screw until it

a b l e total valve travel is about l/4". If ball

touches the pitman arm. Then back off the hand

stud travel exceeds this.. . .cylinder removal and

wheel and turn the pitman arm adjusting screw

adjustment will be required.

one full additional turn toward the pitman arm.

17. Then.. . inspect the rear drag I ink.

2 5 . N o w . . . tighten the stop bolt jam nut

If necessary, adjust it to assure that the steer

. . .which must always be installed as shown.

(C)

wheels are straight with cylinder and steering

Then, turn the hand wheel to contact the adjust-

gear centered, making certain to tighten the lock-

ing screw with considerable force. The pressure

nut shown after the adjustment is made. Tighten

should not rise above the minimum'pressure spec-

the rear drag link ball socket screw (0) to 18-22

ified.

pound feet and back if off to nearest hole.

Repeat the same procedures for the left

turn adjustment.

18. N o w . . . i n s p e c t t h e s t e e r a x l e s t o p l o c k -

replace them. If you replace the tie rods the measurement for the

tie rod is 12 11/16'' from center tie rod. If

When the tachometcr only is being used,

the tie rod stud is loose, tighten the stud nut. The tie rod stud

the same routine is followed except that instead

nut should be torque to 68-82 lbs. ft., then increase to next

of reading pressures, you will read RPHs. With

cotter slot.

the engine running at 500 RPH, turn the hand

1 9 . Now... inspect the steer axle stop lock-

wheel to the extreme right until the RPM drops.

If an axle stop is

nuts (Q) for tighteness.

T h e n . . . . slowly back off the hand wheel until

m i s s i n g . . . i n s t a l l a stop...making certain to

engine speed canes back to 500 RPM.

maintain a 78 degree steer wheel angularity for

sol id tired trucks. For pneumatic tired trucks,

When 500 RPM is reached, hold the hand

the steer wheel anguiarity is 75 degrees.

wheel at this position and screw in the pitman

arm adjusting screw one full additional turn

20. Then . ..place masking tape on right and

toward the pitman arm...and install and tighten

left spindle arm. PI ace tape on the spindle stop

.the adjusting screw jam nut. Now. . . turn the

bolt head, on some model s. Now.. .connect a tach-

hand wheel to contact the adjusting screw with

considerable force. The engine speed should not

ometer and start the engine with the transmission

in neutral. With the engine running at 500 RPM,

decrease. Repeat these same procedures for the

turn the hand wheel full right and full left so

left turn adjustment.

that each steer wheel contacts its axle stop

When the above adjustments have been made,

(stop contacts tape) or until engine speed decrea-

disconnect any gauges used and lubricate a11

ses.

axle and linkage points. Then lower the truck

21. Then.. . shut off the engine and check

to the floor and install the seat assembly,

the masking tape for an imprint. Both tapes

floor board, and side hoods.

If one of the tapes has

should have an imprint.

then the rear drag link is out of

no imprint.. .

adjustment and must be adjusted so that the tape

will be imprinted when the wheel is fully turned.

22. When both tapes are imprinted, we are

ready for final adjustment... .which is the setting

of the pitman arm stops. There are two ways of

d o i n g t h i s . . . . with a pressure gauge or with a

The use of a pressure gauge is pre-

tachometer.

ferred, however, because it provides more accurate

readings.

23. When using a pressure gauge, hook up

the gauge in the pressure line going to the power

steering cylinder.

Now . . .with the parking brake set, the truck

blocked up, the transmission in neutral and the

engine idling, turn the hand wheel to the extreme

r i g h t . . . . until the axle stop makes contact and

you get a sharp rise in pressure. Then back off

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