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Troubleshooting
1. Follow
Pressure Relief Procedure, page 8
2. Check all possible remedies in the
Troubleshooting Chart before disassembling the
pump.
Problem
Cause
Solution
Pump cycles, but no fluid comes out. Fluid supply is empty.
Replace fluid supply.
Air supply flow or pressure is
inadequate.
Improve air supply flow, increase
pressure, or increase air line size.
Air valves are closed or clogged.
Open air line. Use dry air.
Air line is closed or clogged.
Remove obstruction.
Fluid line is obstructed.
Remove obstruction.
Fluid line is too small.
Increase size of fluid line.
Pump cycles, but fluid flow is too
slow.
Fluid is too thick.
Reduce viscosity of fluid by heat or
dilution.
Pump dives and/or does not pump
on upstroke.
Pump rod check seat or seals are
worn out or missing.
Replace check seat or seals.
Inlet check seat or seals are worn
out or missing.
Replace inlet check seat or seals.
Pump dives and/or does not pump
on downstroke.
Fluid inlet is obstructed.
Clear obstructions away from inlet.
Raise pump off of drum bottom.
Pump cycles unevenly or erratically. Air motor is obstructed by ice chunks
or other material.
Remove obstruction. Use dry air.
Pump dives at fast speeds only.
Fluid is too thick, causing cavitation. Reduce viscosity of fluid by heat
or dilution or slow down the pump.
Raise pump off the bottom of the
drum.
Ice has built up in the air motor.
Use dry air.
Air motor has a broken or missing
seal.
Replace air motor seals.
Air motor stalls and hisses air.
Air motor has a broken part.
Replace broken item.
Air motor hisses air while running.
Air motor has a damaged o-ring or
upper gasket.
Replace damaged item.
Throat seals are worn or missing.
Replace throat seals.
Fluid comes out of exhaust port.
Air line contains too much water.
Use dry air.
Pump rod locks up.
Throat cartridge weep hole is
clogged.
Clear.
Cover won’t stay on.
Air motor cylinder has a leak.
Tighten air motor cylinder or cover;
replace square cylinder seals.
10
3A2977K