3-12. AIR BRAKE SYSTEM MAINTENANCE (CONT)
b. Service Brake Treadle and Valve and Declutch Treadle and Valve (Cont).
REASSEMBLY OF BRAKE VALVE (SHEET 1 OF 2)
Apply silicone lubricant to new O-ring (30) and install O-ring in groove
on new valve (32).
Apply silicone lubricant to new O-ring (31) and install O-ring on shoul-
der in bore in bottom of valve body (33).
Install new retainer (29) on valve (32), lip toward rubber end of valve
Install new spring (28) on valve (32). Install new seat (27) on valve
(32), through spring (28).
Using thumb and forefinger, carefully push valve (32) and seat (27) to-
gether so that end of valve goes into seat. Install new spring (26) into
seat (27) and valve (32) so that hook in side of spring (26) makes con-
tact with shoulder inside valve. Be sure spring (26) eye is over screw
hole in bottom of seat (27). Spring must hold valve and seat together.
Install new diaphragm (25) over spring (26) eye and screw hole in bottom
of seat (27).
Place new washer (24) on diaphragm (25) so that inside diameter contacts
Install and tighten new screw (23) to secure washer (24) and diaphragm
(25) to seat (27).
Lubricate piston (22) using silicone lubricant.
Install spring (21) in top of piston (22).
Install new spring seat (20) on top of spring (21).
Apply one drop of retaining compound to three or four threads on one side
of capscrew (18) only.
Install lock washer (19) and capscrew (18). Tighten capscrew to 4 lb-ft.
Apply silicone lubricant to new O-ring (17) and install O-ring in groove
of piston (22).
Install valve assembly (23 thru 32) in valve body (33) bottom bore.
With your forefinger, push valve assembly (23 thru 32) into valve body
(33) bore and install retaining ring (16) in groove in bore in bottom of
valve body using snap ring pliers.
Put valve body (33) on bench so that top of valve body is up.
Install vent filter (15) in groove in top of valve body (33).