TM 5-4310-352-14
b. This manual cannot list all malfunctions that
Table 4-2 lists the common malfunctions that you may
find during the operation or maintenance of the air com-
may occur, nor all tests or inspections and corrective ac-
tions. If a malfunction is not listed or is not corrected by
pressor or its components. You should perform the
tests/inspections and corrective actions in the order listed.
listed corrective action, notify higher level mainte- nance.
4-6. Troubleshooting
Table 4-2. Troubleshooting
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
NOTE
Before you use this Table be sure you have performed normal operational checks. If you have a malfunction which is not listed in this
table, notify the next higher level of maintenance.
1. COMPRESSOR PUMPING OIL
Step 1.
Check for a leaking pilot valve.
Step 2.
Check for a hot cylinder head. If one seems hotter than the other, there could be damaged rings on piston.
Notify direct support maintenance.
2. KNOCKS OR RATTLES
Step 1.
Check for loose belt wheel or motor pulley.
Step 2.
Check for leaking pilot valve, or restrictions in piping system.
Replace a leaking pilot valve (para 4-11). Report restricted piping to direct support maintenance.
3. AIR DELIVERY DROPPING
Step 1.
Check for air leaks in piping.
Make a soapy solution with warm water. Paint on fittings and watch for signs of air leaks. Report leaking fittings, if
tightening does not stop the bubbles, to direct support maintenance.
Step 2.
Check for a leaking pilot valve.
Step 3.
Check for restricted air passages, or leaking or broken valves.
Notify direct support maintenance.
4. MOTOR OVERLOAD RELAY TRIPS
Step 1.
Check line voltage or motor terminals loose connections, or defective starter heaters.
Notify direct support maintenance.
6. EXCESSIVE STARTING OR STOPPING
Step 1.
Check receiver for condensate.
Open draincock at bottom of air receiver, when all air has escaped close draincock.
Step 2.
Check for leaking, broken, or worn pressure switch (fig. 2-1).
Notify direct support maintenance.
6. COMPRESSOR RUNNING HOT
Step 1.
Check that air passage is not blocked at fan wheel.
Move any foreign object that may block ventilation.
Step 2.
Test for a leaking check valve.
Report a defective check valve to direct support maintenance.
7. COMPRESSOR RUNNING SLOW
Step 1.
Check for low line voltage or a defective motor starter heater.
Tighten loose terminals. If still running slow, notify direct support maintenance.
Step 2.
Check for leaking or mal-adjusted pilot unloader valve.
8. LIGHTS FLICKER WHEN COMPRESSOR RUNS
Check terminals of motor.
If bad connections cannot be rectified, notify direct support maintenance.
4-7. General.
consists of a matched pair of belts, and pulleys of a size
a. Motor. The motor is a 115/230 vac, single phase
designed for changing the motor speed of 1,750 rpm to a
60 hertz, induction motor, with initial connections for 115
compressor speed of 610 rpm.
vac.
4-2