PUMP SYSTEM MALFUNCTION
MALFUNCTION
The Pressure and/ or the Delivery Drops
CAUSE
Worn packing seals Broken valve spring Belt slippage
Worn or Damaged nozzle Fouled discharge valve Fouled inlet strainer Worn or Damaged hose
Worn or Plugged relief valve on pump Cavitation
Unloader
REMEDY
Replace packing seals Replace spring Tighten or Replace belt Replace nozzle Clean valve assembly Clean strainer Repair/Replace hose
Clean, Reset, and Replace worn parts Check suction lines on inlet of pump for restrictions
Check for proper operation
Water in crankcase | High humidity | Reduce oil change interval |
| Worn seals | Replace seals |
|
|
|
Noisy Operation | Worn bearings |
| Cavitation |
Replace bearings, Refill crankcase oil with recommended lubricant Check inlet lines for restrictions and/or proper sizing
Rough/Pulsating | Worn packing |
Operation with | Inlet restriction |
Pressure Drop |
|
| Accumulator pressure |
| Unloader |
| Cavitation |
Replace packing
Check system for stoppage, air leaks, correctly sized inlet plumbing to pump Recharge/Replace accumulator Check for proper operation Check inlet lines for restrictions and/or proper size
Pressure Drop at | Restricted discharge plumbing | |
Gun |
| flow rate of pump |
Excessive Leakage | Worn plungers |
| Worn packing/seals |
| Excessive vacuum |
| Cracked plungers |
| Inlet pressure too high |
Replace plungers
Adjust or Replace packing seals Reduce suction vacuum Replace plungers
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 |
10