38
Troubleshooting
Pumping (after satisfactory startup)
Problem Cause
Solution
Pump stalling and no material
being pumped despite
adequate input pressure.
Blocked mixer.
Closed outlet ball valves.
Blocked check valve.
Turn off air supply and remove
hoses from mixer. Check
hoses for flow.
Open ball valves
Unlikely to be fully restricted,
but possible. Dismantle, clean,
and reinstall.
Pumps cycling satisfactorily
but
total material output dropped
off, or one pump output lags
behind the other.
One pump metering
incorrectly.
Check both outputs from the
hoses. If pumps are out of
phase or if one pump is not
discharging a full shot of
material, see next solution.
Pumps not discharging normal
or full volume.
Low material level in
reservoirs.
Air in material (normally only
high viscosity material).
Piston worn or broken.
Check valve malfunction.
Flow controls set differently
Refill reservoirs. Prime pump
and hoses.
Reload reservoir with
minimum air entrapment. (Ask
for technical advice.) See “air
in hose” solution.
Remove and inspect
suspected piston. Replace if
worn, damaged.
Remove, clean, and reinstall
the check valve.
Readjust flow controllers.
Pumps not cycling at all or
pumps not completely cycling.
Air circuit failure.
See Logic Circuit
troubleshooting.
Pumps drawing material back
down from hose.
Check valve stuck open.
Remove check valve and
clean or replace.
