VMAC - Vehicle Mounted Air Compressors
VMAC Technical Support: 888-241-2289
VMAC Knowledge Base: kb.vmacair.com
67
Symptom
Possible Cause
Corrective Action
Engine rpm does not
decrease.
Throttle tube frozen, plugged
or obstructed.
Clean or replace tube.
Throttle actuator failure.
Replace actuator.
Discharge valve failure.
Replace discharge valve.
Inlet regulator pressure set
too close to unloader valve
pressure setting.
Follow the inlet regulator
adjusting steps on page 70.
Flow control valve plugged or
obstructed.
Replace flow control valve.
Symptom
Possible Cause
Corrective Action
Engine rpm does not increase.
Unloader valve manually
activated.
Manually disengage unloader
valve.
Inlet valve regulator pressure
set too low.
Adjust inlet valve regulator to
increase pressure.
Discharge valve failure.
Replace discharge valve.
Throttle actuator failure.
Replace actuator.
Symptom
Possible Cause
Corrective Action
Engine overheat.
High ambient temperatures.
Reduce duty cycle.
Low engine oil level.
Check engine oil level with
equipment on level ground.
Cooling intake plugged.
Correct problem.
Insufficient ventilation.
Correct problem.
Spark arrester fouled.
Clean spark arrester.
Mounted in enclosure.
See enclosure mounting
parameters on page 16.
Symptom
Possible Cause
Corrective Action
Blowdown does not function.
Scavenge tube frozen,
plugged or obstructed
Clean or replace tube.
Blowdown muffler plugged or
obstructed.
Replace muffler.
Blowdown valve failure.
Replace blowdown valve
assembly.
Symptom
Possible Cause
Corrective Action
Oil comes out of the
blowdown muffler.
Operating angle more than
15° from horizontal.
Reduce operating angle.
Compressor oil overfilled
Check oil level with
equipment on level ground.
Faulty blowdown shuttle
valve.
Replace blowdown shuttle
valve.
Blowdown valve failure.
Replace blowdown valve
assembly.
