Quincy Compressor QR-25 Series Instruction Manual page 31

—. ...."--— ..—, —.
—.
—.—. —.——
.—". ——. —.
Trouble
Probable Cause
—
Intercooler pressure
Compressor valves or valve unloaders in fh-st stage not functioning
abnormally low
properly or defective
(Two stage models only)
Restricted air inlet falter or suction line
Pilot valve or pressure switch set incorrectly or defective
Pressurized air at valve unloader not venting properly when demand for
air is required; vent passage at hydraulic unloader or three-way valve
could be plugged
Compressor valve or head gasket leaking
Worn piston rings
Defective pressure gauge
Leaking air at intercooler or intercooler connections
Compressor overheats Clogged intake system
Defective compressor valves
Pressure setting too high
Clogged intercooler, internally or externally
Clogged water passages in cylinder head &/or cylinders
Defective water temperature regulator valve
Inadequate cooling water flow, ventilation, or recirculation of hot air
Pulley/sheave rotation wrong
Incorrect speed
Running clearances insufficient (piston to cylinder wall or running gear)
Lubrication inadequate
Compressor incorrectly sized
High discharge
temperature
Defective water temperature regulating valve
Inadequate cooling water flow
Compressor valve assemblies defective
Discharge pressure too high
Inadequate ventilation or hot air recirculating
Cooling surfaces of compressor or intercooler excessively dirty
Internal surface of heat exchanger fouled
Ambient temperature too high
Scored or excessively worn cylinder walls
Cooling water temperature too hot
Compressor knocks Head clearance insufficient
Piston loose in cylinder bore, cylinder bore worn, piston or piston rings
worn
Worn rods or main bearing
Wrong pressure setting, discharge pressure excessive
Crankcase lubrication inadequate
Loose pulleylsheave
Compressor valve assemblies loose
.._
QR-25 Series QUINCY COMPRESSOR
52201-104 27
February 1994