Quincy Compressor QR-25 Series, Instruction Manual

Page: 32 / 44

QR-25 Series Quincy Compressor
52201-105, May 2003 28 3501 Wismann Lane, Quincy IL - 62305-3116
SECTION 6 SECTION 6
SECTION 6 SECTION 6
SECTION 6 TROUBLESHOOTING TROUBLESHOOTING
TROUBLESHOOTING TROUBLESHOOTING
TROUBLESHOOTING
Trouble Probable Cause
Low discharge pressure •Restricted inlet
•Defective compressor valves or valve unloading mechanism
•Leaks in the compressed air distribution system at fittings, connections,
etc.
•Unloader pilot defective or set wrong
•Pressure switch defective or set wrong
•Drive belt slipping
•3-way valve defective (Model 108)
•Flyweight assembly on crankshaft not functioning properly
•Incorrect speed
•Worn piston rings or loose piston
•Faulty hydraulic unloader
•Leaking head gasket
•Low oil pressure
•Drain valve open
•Defective pressure gauge
•Excessive running clearances
(refer to SECTION 2, Specifications )
•Pressure relief valve leaking
•Clogged intercooler
•Loose compressor valves or leaking at valve gaskets
•Compressor incorrectly sized for the altitude it is operating at
•Piston rings not seated; allow 100 hours at full pressure
Water in the crankcase •Compressor does not run long enough to get hot and vaporize the liquids
(lubricant appears milky) squeezed out of the air during compression
•Leaking water jacket or cylinder head
•Incorrect or inferior grade of lubricant
•Cooling water circulating in compressor too cold
•System pressure leaking back through discharge valve
Rusty valves •Compressor operated too infrequently
and/or cylinders •Compressor does not run long enough to get hot and vaporize the liquids
squeezed out of the air during compression (compressor may be too large
for application)
•Leaking water jacket or cylinder head
•Cooling water circulating in compressor too cold
•Compressor not properly prepared for storage
•Discharge line from compressor head is pointed upward allowing con
densation to drain back at shutdown
Excessive vibration •Incorrect speed
•Compressor valves not functioning properly
•Loose pulley/sheave
•Motor or engine out of balance
•Compressor, motor or engine not secured tightly, or tightened into a
bind
•Foundation or frame inadequate