adjusting nut (fig. 44) clockwise raises both the loading and unloading setting; turning the nut counterclockwise lowers
both settings. The differential pressure (difference between loading and unloading points) is factory set and must not be
changed.
108. Unloader Pilot
a. Removal (fig. 41).
(1) Remove the check and bleed valve (par. 105a).
(2) Remove the control line air filter (par. 106a).
(3) Remove the four hex nuts (13), lockwashers (12) and hex head bolts (8) and lift the unloader pilot (26) from
the mounting bracket (11).
b. Disassembly (fig. 45).
(1) Remove the wing nut (29) and plain washer (28) and lift the side cover (27) from the frame casting (15).
(2) Unhook and remove the trip lever spring (30) and extension spring (33). Take out the screw (31) and
remove the spring stud keeper (32) and valve plunger rod (20).
(3) Unscrew the adjusting nut (17) and remove the adjusting screw (18) and main spring (19) from the frame
casting.
(4) Remove the hex nut (26), lockwasher (25) and trip lever (24) from the trip lever screw (12) and press the felt
washer (23) from between the two arms of the trip lever.
Note: The trip lever stud, which protrudes through the back of the frame casting, supports the
unloader valve plunger pin (6). Be careful not to lose this pin.
(5) Pull out the main arm pivot pin (35) and remove the main arm (34) from the casting.
(6) Disconnect the tubes (13 and 14) from the elbows (11). Unscrew the twelve screws (1, 2, and 3) and
disassemble the outer diaphragm casting (4), diaphragm (40), plunger disk (39) and inner diaphragm
casting (38) from the frame casting. Unscrew the couplings (5) from the outer diaphragm casting.
(7) Remove the two lock nuts. (7) and disassemble the unloader valve (10) from the bracket (8) and the kickoff
valve (16) from the frame casting. Unscrew the elbows (11) from the valves.
c. Cleaning and Inspection.
(1) Clean all parts with thoroughly with a low pressure jet of compressed air. Wipe the exterior of the cover and
castings
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