(4) Loosen the tube fitting (32) to release the tube
(2) Flush out the interior of the reservoir with
from the air compressor assembly (22).
solvent. Repeat until the solvent is no longer
(5) Wrap a sling around the compressor and sup-
discolored after cleaning. Drain thoroughly.
port the compressor weight with a hoist. Remove" the
The air reservoir operates under high
four cap screws (18), nuts (19), lock washers (20), and
air pressure. Making structural
flat washers (21) that secure the air compressor to
the mounting pad on the air reservoir (36). Lift the
repairs to the air reservoir could
weaken it and make it unsafe for use.
compressor from the reservoir with a hoist.
(6) Remove the pipe cap (13) and drain the com-
No repairs to the air reservoir are
pressor oil into a container. Loosen the cap screw (14)
authorized. If it is damaged, you must
and slide the oil trough (15) from the pipe nipple (16)
(3) Inspect the reservoir for cracks, severe dents,
and elbow (17).
(7) Refer to the compressor to direct support
damaged threads, and broken weldments. Replace if
maintenance for repair.
(4) Inspect the safety valve for cracks, dents, and
damaged threads. Pull out on the plunger to check
(1) Installation is the reverse of removal. Refer
that its working parts are free. If possible, check the
relief pressure of the valve. It must relieve at 200 psi.
(2) Install drive belts and adjust tension per
(5) Inspect the check valve for cracks, damaged
threads, and other damage. The check valve must
allow flow in one direction only, Replace a damaged
allow the compressor to build up pressure. Use a soap
bubble solution to check fittings for leaks. Correct
(6) Inspect all remaining parts for cracks,
damaged threads, distortion, and other damage;
replace damaged parts.
c. Reassembly and Installation.
4-43. Air Reservoir and Fittings.
(1) Reassembly and installation is the reverse of
a. Removal and Disassembly.
the directional arrow on the check valve (25) to insure
that flow is in the correct direction.
(4) Disconnect the air piping from the air reser-
(3) Start the engine. Allow air pressure to build
up in the air reservoir. Use a soap bubble solution to
check for leaks. Correct any leaks noted.
(6) Remove the check valve (25) and related fit-
tings (23, 24, 26,27, and 28, fig. 4-9) from the reservoir
4-44. Compressor Pilot Valve
(7) Remove the safety valve (29) and related fit-
a. Adjustment. If the compressor fails to maintain
tings (30 and 31) from the reservoir.
reservoir pressure in the required range (140 to 170
psi), you should adjust the pilot valve as follows:
(8) Use a sling around the reservoir (36) and sup-
port the reservoir with a hoist, Remove the cap
(1) To raise or lower the pressure range without
screws (33), nuts (34), and lock washers (35).
increasing or decreasing the spread of the range,
b. Cleaning and Inspection.
loosen the outside lock nut (1, fig. 4-10) and turn the
adjusting screw (2). If you turn the adjusting screw
(1) Wipe the exteriors of the check valve and
clockwise, you will increase the pressure. Turning it
safety valve with a cloth dampened with dry cleaning
counterclockwise will decrease the pressure.
solvent (fed. spec. P-D-680).