4-14. NO. 8 VENT VALVE (cont)
CLEANING, INSPECTION, AND REPAIR (cont)
Check that spring (21) has not rusted, become distorted, or has taken a permanent set.
Replace damaged parts.
Check that exhaust valve seat (19) is not scratched or scored. If exhaust valve seat is damaged, recondition by
Lap exhaust valve seat (19) with lapping compound using a front-to-back motion.
Use compressed air and remove foreign matter from exhaust valve seat (19).
Use a cloth dampened with drycleaning solvent and clean exhaust valve seat (19).
Check that exhaust valve seat (19) is not cracked or cut. Replace damaged exhaust valve seat.
Use pneumatic grease and lubricate O-rings, O-ring grooves in spool valves, a
nd bushings into which spool valves
enter. Use a clean wiping rag and remove excess lubricant.
Use triple valve oil and lubricate piston stem guides.
Valve assemblies are under a spring load. Use caution during assembly procedures so that no
parts fly out, causing injury to personnel.
Assemble exhaust valve assembly (17) by the following:
Install O-ring (23) on exhaust valve seat (19).
Install O-ring (22) on exhaust valve (20).
Install spring (21), exhaust valve (20), and exhaust valve seat (19) in body (2) and install retaining ring (18).
Assemble piston diaphragm assembly (8) by the following:
Install seal (16) and felt (15) in piston (12).
Install flat washer (13) and piston (12) on piston stem (14). Check that felt (15) is toward threaded end of