Giant P218, P219, P220, P223, P217, P221 service manual Pump System Malfunction

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

Highhumidity

Worn seals

Worn bearings

Cavitation

Worn packing

Inletrestriction

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,andReplacewornparts Check suction lines on inlet of pump for restrictions

Check for proper operation

Reduce oil change interval

Replace seals

Replacebearings,Refillcrankcase oilwithrecommendedlubricant 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

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