Troubleshooting
311304H 11
Motor stalls when nozzle is closed. Bypass relief valve (4a) stuck. Inspect relief valve, making sure
poppet is free. Replace if damaged.
Low supply voltage. Check supply voltage.
Gears (1c/10a) damaged and
binding.
Inspect gears. Gears should turn
freely. Replace if damaged.
Faulty motor. Replace motor.
Fuel leaking in motor mount. Faulty or damaged motor shaft seal
(1g/7d).
Replace shaft seal
Operating pump extended time with
nozzle closed.
Do not exceed 5 minutes of operation
with nozzle closed.
Motor shaft worn. Replace motor if shaft has groove
worn in seal area.
Motor overheating. Gears (1c/10a) 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 strainer (3b). Clean or replace, see Maintenance,
page 9.
Clogged suction tube, hose, or
nozzle.
Inspect and clean if required.
Operating pump more than 30 min-
utes continuous duty.
Limit operation to 30 minutes per
hour.
Switch will not turn pump on. Blown fuse. Replace fuse. 20 amp automotive
fuse (Littelfuse ATO 257020 or
Bussman ATC-20).
Electrical problem. Check that supply voltage is proper
and getting to pump.
Defective switch (8e). Check and replace if defective.
Mechanical problem. Check switch actuator cam (8c). Cam
should be actuating the switch (8e).
Damaged or defective motor. Check motor, replace if damaged or
defective.
Problem Cause Solution