PUMPSYSTEMMALFUNCTION

MALFUNCTION

CAUSE

REMEDY

The Pressure and/or

Worn packing seals

Replace packing seals

theDeliveryDrops

Brokenvalvespring

Replacespring

 

Beltslippage

Tighten or Replace belt

 

Worn or Damaged nozzle

Replacenozzle

 

Fouleddischargevalve

Cleanvalveassembly

 

Fouledinletstrainer

Cleanstrainer

 

Worn or Damaged hose

Repair/Replacehose

 

Worn or Plugged relief valve on pump

Clean,Reset,andReplacewornparts

 

Cavitation

Check suction lines on inlet of

 

 

pumpforrestrictions

 

Unloader

Check for proper operation

 

 

 

Water in crankcase

Highhumidity

Reduceoilchangeinterval

 

Worn seals

Replaceseals

 

 

 

Noisy Operation

Wornbearings

Replacebearings,Refillcrankcase

 

 

oilwithrecommendedlubricant

 

Cavitation

Checkinletlinesforrestrictions

 

 

and/orproper sizing

 

 

 

Rough/Pulsating

Wornpacking

Replacepacking

Operationwith

Inletrestriction

Check system for stoppage, air

Pressure Drop

 

leaks,correctlysizedinletplumbing

 

 

to pump

 

Accumulatorpressure

Recharge/Replaceaccumulator

 

Unloader

Check for proper operation

 

Cavitation

Checkinletlinesforrestrictions

 

 

and/or proper size

 

 

 

Pressure Drop at

Restricteddischargeplumbing

Re-sizedischargeplumbingto

Gun

 

flow rate of pump

 

 

 

ExcessiveLeakage

Wornplungers

Replaceplungers

 

Wornpacking/seals

Adjust or Replace packing seals

 

Excessivevacuum

Reducesuctionvacuum

 

Crackedplungers

Replaceplungers

 

Inlet pressure too high

Reduceinletpressure

 

 

 

HighCrankcase

Wrong Grade of oil

Giant oil is recommended

Temperature

Improper amount of oil in crankcase

Adjust oil level to proper amount

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Giant LP 122A service manual Pumpsystemmalfunction