SECTION 12
TIRE INFLATION SYSTEM
a. in the unloading position, check exhaust
port for inlet valve leakage by applying a soap
solution at the port. Leakage could also be
past the bottom piston grommet.
b. In the compressor operative position,
check the exhaust port to determine leakage at
the exhaust valve seat or grommet. in this
position, leakage could also be past the upper
piston grommet.
12-48. REMOVAL (see figure 12-13).
a. Remove all hoses and cap all openings.
b. Remove the mounting capscrews and
remove the governor.
12-49.
DISASSEMBLY (see figure 12-13).
a. Clean exterior of dirt or grease.
b. Unscrew top cover and remove retaining
ring.
FIGURE 12-13.
and spring
c. Remove adjusting screw
assembly.
to the minimum pressure setting, the spring
loading within the governor overcomes the
d. Remove locknut and upper spring seat
developed force of the air pressure under the
from adjusting screw.
piston. The valve mechanism is actuated,
closing the inlet valve and opening the exhaust
e. Remove pressure setting spring, lower
valve. This shuts off and exhausts the air from
spring gear, spring guide and other lower
the compressor unloading mechanism and
spring seat from adjusting screw.
compression is resumed.
12-44. CHECKS AND ADJUSTMENTS.
f. Remove exhaust stem and spring from top
of piston.
12-45. CHECKING PRESSURE.
g. invert body, tap lightly and the piston
a. Start engine and build up pressure. Note
should fall out.
pressure at time the unloading mechanism
operates.
h. Remove the inlet and exhaust spring and
b. With the engine still running, fill tires
valve from the piston.
with air to reduce tank pressure and note at
I. Remove the two (2) piston grommets, and
what pressure the compressor cuts in. Adjust
with a hooked wire, remove the exhaust from
if necessary.
stem grommet.
12-46. ADJUSTING PRESSURE.
j. Clean or remove filters.
a. Unscrew cover at top and loosen screw
12-50. REASSEMBLY AND INSTALLATION
locknut.
(see figure 12-13).
b. Turn adjusting screw counterclockwise to
a. Prior to assembly lubricate the lower body
r a i s e pressure and clockwise to lower
pressure.
bore, the top of the piston, piston grooves,
grommets, spring guide and adjusting screw.
c. Tighten adjusting screw locknut.
b. Install exhaust stem grommet in its
groove in stem bore of piston.
12-47. LEAKAGE TEST.
12-10.