Troubleshooting
3A8571A
15
The unit pumps, but the output
flow is low.
The inlet suction screen is clogged (used oil).
Remove the inlet suction screen
using a 3/4 in. (19 mm) hex wrench.
Clean or replace the inlet suction
screen.
There is an air leak in the suction tube.
Inspect all joints in the suction tube
making sure that they are sealed.
The suction tube is too close to the tank
bottom.
The suction tube must have a 1 in.
(25.4 mm) minimum clearance.
The tank is empty.
Refill or replace the tank.
The tank is not vented.
Vent the tank to atmosphere.
The gears are worn or damaged.
Inspect the gears. If damaged, replace
the pump housing assembly.
The motor does not run at the proper speed. Check the electrical connection and verify
the supply voltage.
The suction tube, hose, or nozzle is clogged. Inspect and clean the suction tube, hose,
or nozzle, and replace as needed.
Pressure relief is relieving pressure internally.
There is dirt under the pressure relief valve.
Remove the pressure relief valve and
inspect. Clean or replace the pump
housing assembly.
The motor overheats.
The gears are binding.
Make sure that the gears turn freely. If
not, inspect the gears. If damaged,
replace the pump housing assembly.
Pressure relief is relieving pressure internally
at low pressure, not reading pressure switch
set pressure.
Remove and inspect the pressure relief
valve.
Clean or replace the pump.
Operating the pump for more than 30
minutes of continuous duty.
Limit operation to 30 minutes per hour.
Defective pressure switch or electrical
connection is wrong,
Inspect the electrical connection,
, page 10. Replace
the pump outlet assembly with pressure
switch.
Motor cycle On and Off
System pressure is close to the pressure
switch setting.
Reduce system pressure by using a larger
diameter hose or using a less restrictive
dispense valve.
The switch does not turn the
pump on.
The fuse or circuit breaker is blown.
Check the electrical supply.
There is an electrical problem.
Check that proper supply voltage is
getting to the pump. Inspect the electrical
, page
10; and
, page 8.
There is a defective switch.
Replace the pump
The motor is damaged or defective.
The pressure in the system is not being
relieved. The pressure switch is activated.
Relieve pressure by dispensing oil.
Problem
Cause
Solution