INCHING VALVE TEST

TM 10-3930-623-34

NOTE

7. Replace lock screw and assemble valve to

Remove all play or looseness from

pump. Check pressure.

brake pedal and inching rod. Inspect

that pedal stop is actually stopping

8. If still not within range, repeat steps 5, 6 and 7.

the pedal and not the inching valve.

3. Depress brake pedal until inching valve piston is

7-90. POWER STEERING SYSTEM TEST. Road test

fully out. Note point of pedal and determine free play of

the operation of the steering system. The steering wheel

master cylinder push rod.

should turn an equal number of turns right or left from

wheels straight ahead position, with a resistance at the

4. If push rod does not have clearance adjust push

rim of the steering wheel between three and seven

rod end as required.

pounds with the truck stationary and the engine running.

Refer to figure 7-11 for more road test data.

7-88. INCHING VALVE TEST. Assemble necessary

pressure gages to operational tests. See paragraph

7-91.

HYDRAULIC CYLINDER CONTROL VALVE

7-86. With brake pedal fully released, pressures should

Sluggish operation of tilt and lift

ADJUSTMENT.

be as indicated in figure 7-9. Depress pedal until inching

cylinders may result from inproper adjustment of the

valve is fully out. Pressure in front and rear clutch line

control valve relief valve. Disassembly of control will

must show zero pressure.

also require adjustment of the relief valve. Adjust as

follows:

7-89.

POWER STEERING SYSTEM PRESSURE

TEST. After disassembly and assembly of hydraulic

1. Remove pipe plug from adapter (36, figure 4-6)

pump, the system must be bled to remove entrapped air

and install suitable 9-3000 psi gage having 1/4 NPT

and priority valve must be adjusted to provide 1000 psi

male threads.

pressure minimum to the steering system.

Test

pressure as follows:

2. Start engine and operate TILT control lever until

mast reaches limit of travel. Hold lever in operating

1. Rotate steering wheel through full range several

position and note line pressure. Pressure should be

times to remove entrapped air.

1650 psi.

2. Remove plug (7, figure 4-31) in pressure line tee

3. If pressure is not correct, remove cap nut (1)

(8) and install pressure gage.

and loosen locknut (3).

3. Operate engine at fast idle and observe steering

4. T o r ise pressure turn setscrew (4) clockwise

system pressure. If pressure is 1000 and 1200 psi, shut

and to reduce line pressure turn setscrew

down engine, remove gage and replace plug.

counterclockwise.

4. If pressure is not within range adjustment of

5. Recheck pressure as in step 2 and readjust if

priority valve (27 through 31, figure 4-7) is required.

necessary.

5. Remove plug (24) and valve assembly from

6. Holding setscrew, tighten locknut and install cap

hydraulic pump.

nut.

6. Remove lock screw (27) and adjust screw (28).

7. Shut off engine and remove gage.

Replace

Turn in to raise pressure output and backout to reduce

plug.

pressure.

7-24