Giant LP250W-MT - Manual (Page 10)

10
PUMP SYSTEM MALFUNCTION
MALFUNCTION
The Pressure and/or
the Delivery Drops
Water in crankcase
Noisy Operation
Rough/Pulsating
Operation with
Pressure Drop
Pressure Drop at Gun
Excessive Leakage
High Crankcase
Temperature
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
High humidity
Worn seals
Worn bearings
Cavitation
Worn packing
Inlet restriction
Accumulator pressure
Unloader
Cavitation
Restricted discharge plumbing
Worn plungers
Worn packing/seals
Excessive vacuum
Cracked plungers
Inlet pressure too high
Wrong Grade of oil
Improper amount of oil in crankcase
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
Reduce oil change interval
Replace seals
Replace bearings, Refill crankcase
oil with recommended lubricant
Check inlet lines for restrictions
and/or proper sizing
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
Re-size discharge plumbing to flow rate
of pump
Replace plungers
Adjust or Replace packing seals
Reduce suction vacuum
Replace plungers
Reduce inlet pressure
Giant oil is recommended
Adjust oil level to proper amount
Preventative Maintenance Check-List & Recommended Spare Parts List
Check Daily Weekly 50hrs Every Every Every
500 hrs 1500 hrs 3000 hrs
Oil Level/Quality X
Oil Leaks X
Water Leaks X
Belts, Pulley X
Plumbing X
Recommended Spare Parts
Oil Change (1 Gallon) p/n 1154 X X
Oil Seal Kit (1 kit/pump) X
(See page 5 for kit lit)
Valve Spare Parts (1 kit/pump) X
(See page 5 for kit list)