Figure 14. Removing Check Valve Seat

TM 10-3930-644-14&P

Figure 14. Removing Check Valve Seat

Figure 16. Removing Spool From Sleeve

hole end of the housing, and the flat side of the

down (Fig. 19).

end cap.

Stroke each surface across the

abrasive several times and check the results

3. Install check ball into check hole and make sure

(Fig. 18). Any small bright areas indicates a burr

it rests on top of small end of spring.

which must be removed. When polishing the

parts, hold them as flat as possible against the

4. Place the check-valve seat on hex wrench and

abrasive. After 6 to 10 strokes across the

install it in the : Check valve hole so the

abrasive, check the part to see if it is polished.

machined counterbore seats on the ball.

After each part is polished, rinse clean in

Tighten the seat to 150 lb-in (Fig. 20). Check

solvent, blow dry with air, and place it where it

ball action by pushing ball against the spring

can remain absolutely clean until reassembly.

force with a small pin.

D. REASSEMBLY

NOTE

Ball does not nave to be snug against

1. Lubricate all parts lightly with clean hydraulic oil

seat to function properly.

at time of reassembly.

5. Carefully install the spool within the sleeve (Fig.

2. Install housing in vise with control end up and

21). Be sure that spring slots of both parts are

14-hole end resting on a clean wooden block.

at the same end.

Clamp lightly across the port surface and install

check valve spring into check bore with large

end

Figure 15. Loosening Spool Assembly

Figure 17. Removing Spring From Spool

3-166