BLACKMER ProVane PV6B, Installation, Operation And Maintenance Instructions

111-B00    Page 14/16 

GENERAL PUMP TROUBLESHOOTING 

EXCESSIVE NOISE AND VIBRATION 

Probable Cause 

Corrective Action 

Cavitation or vaporization of the liquid resulting from 
excessive vacuum on the pump due to starved suction. 

Check for: 



Inlet piping too long or too small in diameter.  



Strainer plugged or dirty.  



Undersized or restrictive fittings, such as globe valves or partially 
closed valves. 



Excessive amount of elbows.  



Suction lift too great.  



Pump speed too high for the viscosity of the liquid being pumped. 

Entrained air or vapors in the pump. 

Check pipe joints for leakage of air. Sometimes when recirculating 
liquid in a tank, the returning liquid falling through the air carries air 
down into the tank, which eventually gets back into the pump. 

Pump speeds exceed the recommended maximum. 

Check the recommended RPM for your specific application. 

Liner Installed Backwards 

The word “INTAKE”, which is cast on the liner MUST be towards the 
intake side of the pump 

Continual or long term bypassing of liquid through system 
bypass valve. 

Check for restriction in the discharge line, or an improper bypass valve 
adjustment 

OTHER POSSIBLE CAUSES OF NOISE AND VIBRATION: 



Excessively worn vanes 



Bearing Worn or Damaged. 



Loose or improperly installed piping.  



Misalignment of pump and driver. 



Pump base not properly mounted. 

POOR OR NO PRIMING 

Probable Cause 



Air leaks in the suction line.  



Restriction in the suction line.  



Damaged or worn pump parts.  



Too much lift for the vapor pressure of the fluid.  



A dirty or clogged strainer.  



Worn vanes.  



Suction Valve Closed.  



Incorrect pump rotation  



Bypass Valve partially open, valve not seating properly. 

DAMAGED VANES 

Probable Cause 



Foreign objects entering the pump. 



Running the pump dry for extended periods of time. 



 Cavitation. 



Viscosity too high for the vanes and/or pump speed. 



Incompatibility with the liquids pumped. 



 Excessive 

heat. 



Worn or bent push rods, or worn push rod holes. 



Settled or solidified material in the pump at start-up. 



Hydraulic hammer - pressure spikes. 



Vanes installed incorrectly (see “Vane Replacement"). 

BROKEN SHAFT 

Probable Cause 



Foreign objects entering the pump. 



Viscosity too high for the pump speed. 



Bypass valve not opening. 



Hydraulic hammer - pressure spikes. 



 Pump/driver, 

driveline/drive shaft misalignment. 



Excessively worn vanes or vane slots. 



Settled or solidified material in the pump at start-up. 

SEAL LEAKAGE 

Probable Cause 



O-rings not compatible with the liquids pumped. 



O-rings nicked, cut or twisted. 



Shaft at seal area damaged, worn or dirty. 



 Excessive 

cavitation. 



Mechanical seal faces cracked, scratched, pitted or dirty. 



Ball bearings worn. 

MOTOR OVERLOAD 

Probable Cause 



Horsepower of motor not sufficient for application 



Improper wire size / wiring and/or voltage to motor. 



Misalignment in pump drive system. 



 Excessive 

viscosity, 

pressure or speed. 



Faulty or worn bearings. 



Rotor rubbing against head or liner. 



Dirty mechanical seal faces.