Rev. - 922124-01
5
SYMPTOM
PROBABLE CAUSE
CORRECTIVE ACTION
A. SWITCH FAILS TO
OPERATE MOTOR
1. Motor protector activated.
Turn off switch. Allow motor to cool, then turn on switch.
2. Fuse blown.
Inspect fuse in fuse holder on power cord. If blown, replace.
3. Switch or electrical connections faulty.
Inspect for damaged motor protector, defective wiring or switch, or improper
electrical connections. Replace as necessary.
4. Motor burned out.
Inspect and replace as necessary.
B. MOTOR RUNS BUT
DOES NOT PUMP
FLUID
1. Suction pipe clogged, damaged, or
missing.
Remove pump from tank. Inspect suction pipe. Clean or replace, as neces-
sary.
2. Gear coverplate or O-ring damaged
Remove and inspect the coverplate and O-ring. Replace, as necessary.
3. Strainer clogged or defective
Remove strainer coverplate. Remove and clean strainer. Install again.
4. Bypass poppet O-ring worn, missing
Inspect O-ring using instructions in the Repair Section. Replace, if necessary.
5. Bypass poppet O-ring dirty
Remove poppet assembly and clean poppet and cavity.
6. Bypass poppet binding or damaged
Using instructions in the Repair Section, remove the bypass poppet, spring,
and O-ring. Clean cavity. Inspect and replace components, as necessary.
7. System air leak
Tighten all pump fittings and connections. Inspect suction pipe for leaks or
damage.
8. System air lock
This can occur if external filter, meters, or an off-the-shelf automatic
nozzle is used. To correct, remove the pipe plug in the top outlet port and
fill the gear cavity with fuel. Use of a factory-supplied automatic nozzle is
recommended.
9. Poor connections or low voltage
Make sure electrical connections are secure. Also check battery voltage.
10. Fuel level low
Fill tank.
11. Motor running backwards due to incor-
rect polarity
Connect red wire to positive (+) ungrounded side of battery. Gear with key
should turn counterclockwise.
C. LOW FLOWRATE
1. Poor connections or low voltage
Make sure electrical connections are secure. Also check battery voltage.
2. Strainer partially clogged
Remove the strainer coverplate. Remove and clean the strainer. Install again.
3. Suction pipe clogged or damaged
Remove pump from tank. Inspect suction pipe. Clean or replace, as necessary.
4. Fuel tank empty
Fill tank.
5. Using off-the-shelf automatic nozzle
Factory-supplied automatic nozzle is recommended.
6. System air leak
Tighten all pump fittings and connections. Inspect suction pipe for leaks or
damage. Replace, as necessary.
7. Bypass poppet spring weak
Using instructions in the Repair Section, remove the bypass poppet and
inspect spring. Replace, if necessary.
D. MOTOR STALLS
WHEN OPERATING
IN BYPASS MODE
1. Motor protector activated
Turn off switch. Allow motor to cool, then turn on switch.
2. Gears locked
Remove gear coverplate and inspect gears and drive key. Make sure gears
turn freely with the key removed. Replace, if worn.
3. Wiring defective
Use Wiring instructions in the Installation Section to ensure proper connections.
4. Bypass poppet binding or damaged
Using instructions in the Repair Section, remove the bypass poppet, spring,
and O-ring. Clean cavity. Inspect components and replace, as necessary.
5. Motor defective
Replace motor as described in the Repair Section.
E. SWITCH FAILS TO
OPERATE MOTOR
1. Switch or electrical connections faulty
(Model M-240S)
Inspect for a blown fuse, defective wiring or switch, or improper electrical
connections. Replace or install again, as necessary. Refer to Switch Re-
placement instructions in the Repair Section.
2. Motor burned out
Replace motor as described in the Repair Section.
3. Motor protector activated
Turn off switch. Allow motor to cool, then turn on switch.
4. Switch or electrical connections faulty
(Models M-150S and M-180S)
Inspect for damaged motor protector, blown fuse, defective wiring or switch,
or improper electrical connections. Replace as needed and re-install.
F. RAPID OVER-
HEATING OF
MOTOR
1. Duty cycle too long
Pump operation should not exceed the standard duty cycle of 30 minutes
ON, and 30 minutes OFF. Allow the pump to cool for 30 minutes.
2. Strainer clogged
Remove strainer coverplate. Remove and clean strainer. Install again.
3. Suction pipe clogged or damaged
Remove pump from tank. Inspect suction pipe. Clean or replace, as necessary.
4. Gears worn
Remove gear coverplate and inspect gears and drive key. Make sure gears
turn freely with key removed. Replace, if necessary.
5. Fuel level low
Fill tank.
6. Running too long in bypass mode
Limit bypass operation to 10 minutes.
TROUBLESHOOTING
