Hydraulic Valve, Pressure Check

TM 10-3930-630-34

b. Disconnect the hydraulic hose at the inlet

(12) Turn lift section (39) on its side and

install new packings (3 and 4), seal (5), retainer (6) and

port of the control valve and install a tee fitting on the

shim (7) in the grooves in the body. Use petroleum jelly

tube. Connect fitting to adapter in the inlet port. (See

to hold seals in place.

figure 3-8.)

(13) Carefully place tilt section (23) in

c. Install a pressure gage with a 0 to 3000 psi

position on top of lift section (39).

(210.9 kg/cm2) range in the tee.

(14) Coat screw threads with Loctite and

d. Place shift lever in neutral position, turn

install four screws (2) through both sections. Install four

ignition switch on and start engine. Pull tilt lever back to

nuts (1) and torque to 15 foot pounds (20.3 N

retract lift cylinders and hold lever in this position.

b. Installation.

e. Observe the needle on the pressure gage.

When pressure reading of 1950 psi is reached, the

(1) Install plugs, poppets, and adapters

needle should stop, indicating relief valve opening.

re- moved before disassembly.

If relief valve opens below or above 1900

(2) Position control valve on support (fig.

3-6) and secure with three screws, lock washers and

to 2000 psi (133.5 to 140.6 kg/cm2), it must be

nuts.

corrected as follows:

(3) Uncap and connect hydraulic lines to

(1) Turn ignition switch off.

control valve.

(2) When pressure reads zero, remove

(4) Refer to TM 10-3930-630-12 and

relief valve plug and remove valve spring and relief

connect the control valve lever linkage.

valve assembly. Inspect parts for damage and replace

(5) Operate

control

levers

for

defective parts.

approximately 5 minutes to eliminate any air present in

(3) Install valve assembly, new spring

the system. Refer to TM 10-3930-630-12 and bleed the

and plug with new packing.

hydraulic system.

g. Repeat steps d and e of this paragraph.

h. Turn ignition switch off and remove

3-21.

Hydraulic Valve, Pressure Check

pressure gage and tee. Connect hydraulic hose to the

fitting at the inlet port of the control valve.

a. Remove right hand cowl to gain access to

the control valve.

3-12