10
PUMP SYSTEM MALFUNCTION
MALFUNCTION
C A U S E
REMEDY
The Pressure and/
Worn packing seals
Replace packing seals
or the Delivery
Broken valve spring
Replace spring
Drops
Belt slippage
Tighten or Replace belt
Worn or Damaged nozzle
Replace nozzle
Fouled discharge valve
Clean valve assembly
Fouled inlet strainer
Clean strainer
Worn or Damaged hose
Repair/Replace hose
Worn or Plugged relief valve on pump
Clean, Reset, and Replace worn parts
Cavitation
Check suction lines on inlet of
pump for restrictions
Unloader
Check for proper operation
Water in crankcase
High humidity
Reduce oil change interval
Worn seals
Replace seals
Noisy Operation
Worn bearings
Replace bearings, Refill crankcase
oil with recommended lubricant
Cavitation
Check inlet lines for restrictions
and/or proper sizing
Rough/Pulsating
Worn packing
Replace packing
Operation with
Inlet restriction
Check system for stoppage, air
Pressure Drop
leaks, correctly sized inlet
plumbing to pump
Accumulator pressure
Recharge/Replace accumulator
Unloader
Check for proper operation
Cavitation
Check inlet lines for restrictions
and/or proper size
Pump Pressure as
Restricted discharge plumbing
Re-size discharge plumbing to Flow
Rated, Pressure
Rate of Pump
Drop at Gun
Excessive
Worn plungers
Replace plungers
Leakage
Worn packing/seals
Adjust or Replace packing seals
Excessive vacuum
Reduce suction vacuum
Cracked plungers
Replace plungers
Inlet pressure too high
Reduce inlet pressure
High Crankcase
Wrong Grade of oil
Giant oil is recommended
Temperature
Improper amount of oil in crankcase
Adjust oil level to proper amount
