Section V. TILT LOCK VALVE

TM 10-3930-632-34

Tag the spools to assure that each will be

crocus cloth. If burrs and scores are deep, replace valve

assembly.

reassembled in the body from which it was removed. Do

Inspect the C-washers (10, fig. 4-4 and 6, fig.

not interchange the spools in the bodies.

To remove the check valve assemblies, grip

4-5) and spring (4) for distortion, cracks, breaks, or other

damage; if parts are damaged, remove the C-washers

the stem of the check valve with a pliers and pull out the

from the spool and replace with four new C-washers.

plug to release the spring and ball.

Coat parts lightly with engine oil. Check the

relief valve and check valve balls for freedom of

WARNING

movement in their bores. If the relief valve or ball is not

free to move, replace the relief valve or ball.

Dry cleaning solvent P-D-680 is toxic and

flammable. Wear protective goggles and gloves

4-19.

Reassembly

and use only in a well ventilated area. Avoid

contact with skin, eyes, and clothes and don't

Refer to figure 4-4 and 4-5 and reassemble the hydraulic

breathe vapors. Do not use near open flame or

control valve. Note the following:

excessive heat. The flash point is 100F -

Lubricate all parts with clean engine oil prior to

138F. (38C -59C). If you become dizzy while

Reassembly.

Make sure that spools are installed into the

using cleaning solvent, get fresh air immediately

bores of the bodies from which they were removed.

and get medical aid. If contact with eyes is

Install one C-washer (10 and 6) on the spool

made, wash your eyes with water and get

and position the spring (4) on the spool. Compress the

medical aid immediately.

spring and install the second C-washer to retain the

spring.

4-18.

Cleaning and Inspection

When joining the valve bodies together, tighten

Discard all seals and preformed packings;

the nuts on the bolts evenly and alternately to 15 ft/lbs

replace with new parts.

torque.

Clean all metal parts in cleaning solvent P-D-

680 and dry thoroughly with compressed air.

4-20.

Installation

Inspect the two spools of the control valve for

Position the hydraulic control valve on the

distortion, cracks, wear, or scoring. Coat the spool lightly

truck; secure with three capscrews, nuts, and

with clean oil and check the fit of the spool in the body.

lockwashers.

The parts must provide a close-tolerance fit. If any side

Install the control linkage on the control valve.

play of the spool is perceptible, or if the spool is

Connect the hydraulic lines to the hydraulic

damaged, or sticks in the body, replace the entire valve

control valve (TM 10-3930-632-12).

section.

Inspect all parts of the hydraulic control valve

for burrs; remove burrs by lapping with crocus cloth.

Inspect the valve bores for burrs and scoring;

if scores and burrs are not deep, remove them with

Section V. TILT LOCK VALVE

Paragraphs 4-21, 4-22, 4-24, 4-25 and 4-26 deleted.

4-23.

Removal

Remove the tilt block valve (TM 10-3930-632-12).

Figure 4-6. Tilt Lock Valve, Exploded View.

Change 1 4-10