18
8.6 Troubleshooting
PROBLEM
CAUSE
SOLUTION
1- Pump cycles at
stall or fails to hold
pressure at stall.
Worn check valve balls, seats or o-
rings.
Replace.
2- Pump will not
cycle, or cycles once
and stops.
Air valve is stuck or dirty.
Disassamble and clean air valve.
Use ONLY filtered air.
Check valve ball severely worn and
wedged in seat or manifold.
Replace ball and seat.
Check valve ball is wedged into seat,
due to overpressurization.
Install a pressure relief valve.
Dispensing valve is clogged.
Relieve pressure and clean
valve.
3- Pump operates
erratically.
Suction line is clogged.
Inspect; clean.
Sticky or leaking ckeck valve balls.
Clean or replace.
Diaphragm is ruptured.
Replace.
Pump is sucking air.
Check inlet hose and inlet
manifold o-rings.
Restricted exhaust.
Remove restriction.
4- Air bubbles in
fluid.
Suction line is loose.
Tighten.
Diaphragm is ruptured.
Replace.
Loose inlet manifold, damaged seal
between manifold and seat, or damaged
o-rings.
Tighten manifold bolts, or replace
seats or o-rings.
Loose diaphragm shaft bolt.
Tighten or replace.
Damaged o-ring.
Replace.
5- Fluid in exhaust
air.
Diaphragm is ruptured.
Replace.
Loose diaphragm shaft bolt.
Tighten or replace.
Damaged o-ring.
Replace.
6- Pump frequently
stops running.
Insufficient hose diameter.
Get a larger diameter hose.
Too much hose length.
Use a shorter hose.
7- Pump stops
working and
exhausts air.
Air valve is stuck or dirty.
Disassamble and clean air valve.
Use filtered air.
Air valve z-rings are worn.
Disassamble and replace z-rings.
Pilot valve o-rings are worn.
Disassamble and replace o-rings.
Air inlet pressure and flow are not
enough.
Rise the pressure and flow.
8- Pump leaks fluid
externally from
manifold body
connects.
Loose manifolds, damaged o-ring
between manifold and seat.
Replace o-rings, tighten manifold
bolts.
9- Diaphragm moves
to inside of the
pump, and fluid
leaks from the
openings.
Fluid outlet is clogged or outlet valve is
closed when the pump is under
pressure.
Clean the outlet line or open the
fluid outlet valve.
Max. air pressure is exceeded.
Lower the air pressure.
The fluid temperature is above the
working limits. Adjust the air pressure
according to the fluid temperature.
Lower the air pressure.
