Displacement
Pump
Problem
Cause
Solution
Pump fails to
operate
Restricted line or
inadequate air supply.
Clear; use higher air
supply.
Obstructed fluid hose;
fluid hose ID is too small.
Clear; use hoes with
larger ID.
Fluid dried on the
displacement rod.
Clean.
Dirty or worn air motor
parts.
Clean or repair.
Pump operates,
but output low on
both strokes
Restricted line or
inadequate air supply.
Clear; use higher air
supply.
Obstructed fluid hose;
fluid hose ID is too small.
Clear; use hoes with
larger ID.
Bleed valve open.
Close.
Air leaking into supply
container.
Check wiper plate seal.
Worn packing in
displacement pump.
Replace pickings.
Pump operates
but output low
on down stroke
Held open or worn intake
valve or seals.
Clear valve; replace
seals.
Pump operates,
but output low on
up stroke
Held open or worn
piston valve or seals.
Clean, repair a fluid
pump.
Erratic or
accelerated pump
speed
Exhausted fluid supply.
Change the pails.
Held open or worn
piston valve or seals.
Clear valve; replace
seals.
Worn packing in
displacement pump.
Replace pickings.
COSMOSTAR
Fluid Handling Equipment
e-mail:
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TROUBLE SHOOTING
