TM -4310-312-14
open flame or excessive heat. Flash
point of solvent is 100 (38 ) - 138OF
F
C
(5O C).
(1) Remove dust and dirt from motor with
brushes or vacuum Use a cloth dampened in cleaning sol-
vent, Fed. Spec P-D480 to wipe off the stator frame.
(2) Use the same method of cleaning on end
covers and the motor starter.
c. Inspection of Rotor.
(1) Inspect the shaft for movement (end play).
(2) Notify organizational maintenance of a de-
fective rotor, for motor replacement.
d. Inspection of Motor Starter.
(1) Inspect inside cover for loose wires, or other
defect.
(2) Report defective motor starter to direct sup-
port maintenance.
3-11. Air Compressor
a. General. The compressor unit part of the assem-
bly, kept clean and lubricated, should be relatively free of
maintenance. However, if the on-off cycles are too frequent
because of heavy use, and accumulations of dust and dirt
occur covering the frame, intercooler, or aftercooler, the
compressor will run hot. Excessive heat consumes com-
pressor oil. Low oil causes ring wear, or cylinder scoring.
Therefore, frequent inspections are necessary.
b. Inspection.
(1) Visually inspect for excess accumulations of
dust, dirt or film of oil.
(2) Test for heat by touching intercooler tube,
Figure 3-4. Outlet air filter.
aftercooler tube, or cylinder head.
(3) Check pilot valve for signs of leaking.
(3) Inspect holes in filter element for clogging,
(4) Listen for excessive start-stop cycling.
replace defective bowl gasket filter element or defective
(5) Listen carefully for a knock or rattle that
baffles
might signify internal damage.
(4) Use proper parts kit to replace defective
(6) When any of these inspections disclose ab-
items.
normal conditions, refer to Table 3-3 above.
(5) Install bowl (2) in heater and junction box (4)
and secure with screws (8).
3-12. Pilot Valve
(6) Tighten clamp retaining tube to outlet filter
a. General. The pilot valve is a part of the compres-
draincoek (fig. 1-2).
sor unloading system. As the compressor stops the thrust
(7) Tighten bowl locking nut (1, fig. 3-4) with a
pin moves outward, which unseats the valve core and al-
spanner wrench.
lows pressure to bleed off cylinders through the pilot valve
(8) Report defective outlet air filter to direct
tube line and gaps between pilot valve body and its boss.
support maintenance for replacement.
Without this unloading procedure, starting the compressor
would likely cause the overload relay to trip and excessive
3-10. Motor (and Related Parts)
wear on the belts and motor bearing. A leaking, or malad-
a. General.
Crew/operator maintenance of the
justed pilot valve will keep the compressor from unloading
motor consists of cleaning, and inspection of rotor and
when stopped.
moor starter.
b. Cleaning.
valve, refer to figure 3-5 and proceed as follows:
WARNING
Dry cleaning solvent, P-D40, used to
clean parts is potentially dangerous to
personnel and property. Do not use
near
3-10
