Troubleshooting
311305E 7
Unit pumps but output flow is
low.
Clogged inlet suction screen
(used oil).
Clean or replace.
Air leak in suction tube. Check to make sure all joints in
suction tube are sealed.
Suction tube too close to tank
bottom.
Suction tube must have a 2 in.
(51 mm) minimum clearance.
Tank empty. Refill tank.
Tank not vented. Tank must be vented to atmo-
sphere.
Worn or damaged gears. Remove cover and inspect
gears. Replace if worn or dam-
aged.
Damaged motor. Replace motor.
Clogged suction tube, hose, or
nozzle.
Inspect and clean.
Motor stalls when nozzle is
closed.
Bypass relief valve is stuck. Inspect relief valve, making
sure ball is free. Replace if
damaged.
Low supply voltage. Check supply voltage.
Gears damaged and binding. Inspect gears. Gears should
turn freely. Replace if dam-
aged.
Faulty motor. Replace motor.
Motor overheating. Gears binding. Check to make sure gears turn
freely on shaft.
Operating pump extended time
with nozzle closed.
Do not exceed 5 minutes of
operation with nozzle closed.
Clogged inlet suction screen. Clean or replace.
Clogged suction tube, hose, or
nozzle.
Inspect and clean if required.
Operating pump more than 30
minutes continuous duty.
Limit operation to 30 minutes
per hour.
Switch will not turn pump on. Blown fuse or circuit breaker. Check electrical supply.
Electrical problem. Check that supply voltage is
proper and getting to pump.
Defective switch. Check and replace motor (9) if
defective.
Damaged or defective motor. Check motor, replace if dam-
aged or defective.
Problem Cause Solution