Figure 2-1. Control Valve

TM 10-3930-644-14&P

Figure 2-1. Control Valve

1. Install the back-up ring and then the O Rings on

5. Install the O Ring-in the end cap groove and

the fitting. Tighten the fitting securely, but DO

install the cap, switch bracket (if used) and

NOT over tighten.

attaching screws. Torque the screws securely.

On models with detents, grease all the detent

2. Install the O Ring on the relief valve plug. Place

parts. Install the end cap and check for proper

the relief valve assembly in its bore, hex nut end

spool extension alignment. Install the piston,

up. Install the spring and plug and tighten the

spring and plug. Be sure to screw the plug in all

plug securely but DO NOT over tighten.

the way.

3. Install a new back-up ring and O Ring on the

CAUTION

check valve plug with the O Ring toward the

Make sure all mating surfaces of

spring and ball. Place the ball and spring in the

valve bodies are free of burrs and

body and install the plug. Be sure the hole in

paint.

the plug lines up with the stud hole in the body.

Check valves are not used in "8" spool sections.

6. Install seal rings and the seal ring retainer in the

grooves in the body of each inlet and center

4. If the centering spring was removed, install the

section. Use petroleum jelly to hold the seals in

spring and retainers on the spool. Place the O

place. Carefully place the sections together in

Ring in the groove around the spool bore and

the same order in which they were removed.

install the O Ring on the spool. Install the spool

Coat the stud threads with "Loctite" or similar

in the bore.

sealant and install the studs. Tighten the nuts to

15 lb ft torque. If levers are used, install pins in

3-183