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Troubleshooting
Troubleshooting
Troubleshooting
Problem
Problem
Problem
Cause
Cause
Cause
Solution
Solution
Solution
Pump is running too fast, causing
cavitation before prime.
Lower inlet pressure.
Check valve ball is severely warn
or wedged in seat or manifold.
Replace ball and seat.
Seat is severely worn.
Replace ball and seat.
Outlet or inlet is clogged.
Unclog.
Inlet or outlet valve is closed.
Open.
Inlet fittings or manifolds are loose.
Tighten.
Pump cycles but will not prime.
Manifold o-rings are damaged.
Replace o-rings.
Pump cycles at stall or fails to hold
pressure at stall.
Check valve balls, seats or o-rings
are worn.
Replace.
Spool valve is stuck or dirty.
Disassemble and clean air
valve. Use clean dry air.
Air supply pressure too low.
Increase air supply pressure.
Spool valve is worn or damaged.
Replace spool valve.
Check valve ball is severely worn
or wedged in seat or manifold.
Replace ball and seat.
Dispensing valve is clogged.
Relieve pressure and clear valve.
Pump will not cycle, or cycles once
and stops.
Diaphragm is ruptured.
Replace.
Suction line is clogged.
Inspect; clear.
Check valve balls are sticky or
leaking.
Clean or replace.
Diaphragm is ruptured.
Replace.
Exhaust is restricted.
Remove restriction.
Spool valve is damaged or worn.
Replace spool valve.
Air supply is erratic.
Repair air supply.
Pump operates erratically.
Exhaust muffler is icing.
Use drier air supply.
Suction line is loose.
Tighten.
Diaphragm is ruptured.
Replace.
Manifolds are loose, or seats or
manifold o-rings are damaged.
Tighten manifold bolts or replace
seats and/or o-rings.
Diaphragm glide seals or o-rings
are damaged.
Replace.
Air bubbles in fluid.
Pump is cavitating.
Reduce pump speed, increase
suction hose diameter, or increase
inlet head.
Exhaust air contains fluid being
pumped.
Diaphragm is ruptured.
Replace.
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334793A