-15-Model H3370/H3371Air Compressors
TROUBLESHOOTING
Pump motor
will not start
Pump motor
starts; but
fuses blow or
circuit break-
ers trip.
Low pressure
at the tool
Low pressure
at the tanks
Compressor
knocking
Motor runs hot
1. Check power line for proper voltage.
2. Inspect all lead connections on motor,
switch and cord for loose or open connec-
tions.
3. Motor will not start if tank pressure is too
high.
4. Thermal overload switch has tripped, wait
for motor to cool, then reset switch by
pressing red button.
1. Inspect cord or plug for damaged insula-
tion and shorted wires.
2. Inspect all connections on motor for loose
or shorted terminals or worn insulation.
3. Install correct fuses or circuit breakers.
1. Check air hoses and all connections for
leaks.
2. Check pressure in line with known good
gauge.
3. Adjust pressure regulator, if no improve-
ment inspect regulator for leaks or
replacement.
1. Check air tanks, pipes and all connections
for leaks.
2. Close drain valve.
3. Replace safety valve.
4. Inspect and clean air filter.
5. Check gaskets on cylinder head assem-
bly, repair or replace as needed.
6. Inspect and replace pump piston rings.
1. Check oil level and add oil.
2. Inspect and clean air filter.
3. Inspect and repair piston and connecting
rod.
1. Clean cylinder fins and motor area.
2. Inspect and clean air filter.
PROBLEM
CAUSE
ACTION
1. Low voltage.
2. Open circuit in
motor, switch or
cord.
3. Tank already pres-
surized.
4. Thermal overload
switch.
1. Short circuit in line
cord or plug.
2. Short circuit in motor
or loose connec-
tions.
3. Incorrect fuses or
circuit breakers in
power line.
1. Air leaks in flexible
hoses.
2. Pressure gauge bad.
3. Pressure regulator
bad.
1. Air leaks in tanks or
delivery pipes.
2. Drain valve open.
3. Safety valve releas-
ing below 125 PSI.
4. Air filter clogged.
5. Gaskets leaking.
6. Worn rings.
1. Improper oil level.
2. Air filter clogged.
3. Piston assembly
loose.
1. Cooling fins dirty.
2. Air filter clogged.