5-38. AIR DRYER-Continued
(2) Inspect the interior and exterior of ail metal parts that will be reused for severe corrosion, pitting and
cracks. Superficial corrosion and/or pitting on the exterior portion of the upper and lower body halves is
(3) Inspect the bores of both the end cover (32) and the purge valve housing (31) for deep scuffing or
(4) Make certain that all purge valve housing and end cover passages are open and free of obstructions.
(5) Inspect the pipe threads in the end cover (32). Make certain they are clean and free of thread sealant.
(6) Inspect the purge valve housing (31) bore and seats for excessive wear and scuffing.
(7) Inspect the purge valve piston seat for excessive wear.
(8) Inspect all air line fittings for c6rrosion. Clean all old thread sealant from the pipe threads.
(9) All O-rings removed should be discarded and replaced with new O-rings provided in appropriate kit(s).
Any component exhibiting a condition described in steps (1
through 9) should be replaced.
(1) Prior to assembly, coat all O-rings, O-ring grooves, and bores with a generous amount of barium base
lubricant (Item 51; Appendix E).
(2) Purge valve housing assembly.
(a) Install the O-ring (21) in its groove on the outside diameter of the purge piston. Place the return
spring (36) in the bore of the purge valve housing (31). Install the Torx head bolt (14) into the I.D.
of the purge piston. Insert the purge piston (19) into the I.D. of the spring (20). Using a Torx head
wrench engaged on head of Torx head bolt (14), push the piston into the purge valve housing until
(b) While depressing the purge piston with the 12 point socket, install the following parts over the
purge valve bolt (14) from the opposite end of the purge valve housing: the purge valve (18) with
its rubber side first, followed by the diaphragm (17) and the diaphragm washer (16) and finally the
hex nut (15). Torque the purge valve nut (15) and bolt (14) to between 60-80 in lbs (7-9 Nm).
(c) Install the three O-rings (10, 11 and 12) on the purge valve housing placing each in its appropriate
location. If the exhaust cover (13) was removed during disassembly, install it on the purge valve
housing assembly making certain the "bubble" portion is positioned over the thermostat. Install the
assembled purge valve housing (31) in the end cover (32) making certain to orient both parts such
that the connector is approximately 10 degrees clockwise from the supply port, while making
certain the purge valve housing is fully seated against the end cover (32). Secure the purge valve
housing to the end cover using the three self-tapping screws (9). Start all three screws by hand,
then torque to 85-125 in lbs (10-14 Nm).