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Power-Flo Pumps & Systems • 877-24PUMPS • www.powerflopumps.com
Risk of electric shock. Always disconnect the pump from the power source before handling inspections or repairs.
Symptom
Possible Cause(s)
Corrective Action
Little or no discharge and will not prime
1. Pump body not filled with water
2. Total head too high
3. Suction head higher than pump designed for
4. Impeller partially or completely plugged
5. Leak in suction line
6. Foot-valve too small
7. Impeller damaged
8. Foot-valve or suction line not submerged deep
enough in water, pulling air
9. Insufficient inlet pressure or suction head
10. Suction piping too small
11. Body gasket leaking
12. Suction or discharge line valves closed
13. Piping damaged
14. Clogged strainer or foot-valve
1. Fill pump body with water.
2. Shorten suction head
3. Lower suction head, install foot-valve and prime
4. Disassemble pump and clean out impeller
5. Repair or replace suction line
6. Match foot-valve size to piping or install one
larger size foot-valve
7. Disassemble pump and replace impeller
8. Submerge lower in water
9. Increase inlet pressure by adding more water to
tank or increasing back pressure by turning gate
valve on discharge line partially closed.
10. Increase pipe size to pump inlet size or larger
11. Replace
12. Open
13. Clean or replace
14. Clean or replace
Loss of suction after satisfactory operation
1. Air leak in suction line
2. When pump was last turned off, water siphoned
out of pump body
3. Suction head higher than pump designed for
4. Insufficient inlet pressure or suction head
5. Clogged foot-valve, strainer or pump
6. Defective wearplate
1. Repair or replace suction line
2. Refill (re-prime) pump body before restarting
3. Lower suction head, install foot-valve and prime
4. Increase inlet pressure by adding more water to
tank or increasing back pressure by turning gate
valve on discharge line to partially closed.
5. Unclog or replace
6. Replace
Pump overloads driver
1. Total head lower than pump rating, unit
delivering too much water
2. Specific gravity and viscosity of liquid being
pumped different than the pump rating
1. Increase back pressure by turning gate
valve on discharge line to partially closed
position that will not overload motor.
2. Consult factory
Pump vibrates and/or makes excessive noise
1. Mounting plate or foundation not rigid enough
2. Foreign material in pump causing unbalance
3. Impeller bent
4. Cavitation present
5. Piping not supported to relieve any strain on
pump assembly
1. Reinforce
2. Disassemble pump and remove
3. Replace impeller
4. Check suction line for proper size and check
valve in suction line if completly open, remove
any sharp bends before pump and shorten
suction line
5. Make necessary adjustments
Pump runs but no fluid
1. Air leak in suction piping
2. Pump located too far from fluid source
3. Gate valve closed
4. Clogged strainer
5. Fouled foot-valve
6. Discharge height too great
7. Fouled impeller
8. Faulty mechanical seal
1. Replace
2. Replace
3. Open
4. Clean or Replace
5. Clean or Replace
6. Lower the height
7. Clean or Replace
8. Replace
Pump leaks at shaft
1. Worn mechanical seal
2. Seal not installed properly
1. Replace
2. Follow service instructions for installing seal
NOTE:
Power-Flo Pumps & Systems assumes no responsibility for damage or injury due to disassembly in the field. Disassembly of the pumps or supplied
accessories other than at Power-Flo Pumps & Systems or its authorized service centers, automatically voids warranty.
Trouble Shooting Chart
PF5CU, 7CU
Self-Priming Universal Pumps
