4-22. AIR SYSTEM - Continued
Using a hooked wire remove and discard O-ring (13) from the inside of the piston.
Disengage inlet/exhaust valve spring (17) from recess in bottom of piston. Remove spring (17) and the
inlet/exhaust valve (16).
Remove filters (19) from unloader and reservoir ports.
Discard cover (1), inlet/exhaust valve (16), spring (17), both filters (19), exhaust stem O-rings (13), and
piston O-ring (14).
Clean and inspect remaining parts for wear, score marks, or other deterioration. Replace any parts failing
Lubricate body bores, new O-rings, and O-ring grooves with petroleum jelly (item 21, Appendix E).
Install O-ring (13) in piston (15).
Drop the new inlet/exhaust valve (16) into the piston and position the spring (17), small end against the
valve, in the piston. Press the spring down until the larger coiled end snaps into the recess inside the
Install O-rings (14) on outside of piston (15)
Install the washer (12) and the exhaust stem spring (11) into the piston with the large coil end next to the
Install the exhaust stem (10) through spring (11) and into piston (15).
Install assembled piston into the governor body (18).
If the spring assembly was not disassembled proceed to step 25.
Install lower spring seat (7), spring guide (8), spring seat (7), pressure setting spring (6), and upper spring
seat (5) onto adjusting screw (9). Be sure they are installed in the above order.
Screw down the upper spring seat (5) until distance from top of seat to bottom of adjusting screw is 1 7/8
in. (48 mm).
Install the locknut (4).
Install the adjusting screw and spring assembly into the governor body (18).
Install retaining ring (3) making sure it seats completely into the groove in body (18).
Install cover O-ring (2) in cover (1) and screw onto adjusting screw. Tighten until cover bottoms onto
Install filters (19) In governor body.
Install and test governor on compressor as detailed in INSTALLATION preceding.