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Common Causes of Pump Problems
Symptoms
Possible Causes
Suggested Solutions
Excessive Gland
Leakage
Noisy
Excessive Heat
W
ear
Starts, Then
Loses Prime
Fails to Pump
Low Flow
Takes T
oo Much
Power
X
X
X
Suction line high for vapor
pressure of liquid
Reduce vacuum
requirements
X
X
X
Liquid too viscous for pump
speed
Reduce pump speed
X
X
X
Air leakage in suction piping
Tighten and seal all joints
X
X
Suction pipe not immersed
in liquid
Lengthen suction pipe or add
liquid to supply tank
X
X
Suction strainer clogged or of
insufficient area
Clean strainer or use larger
size
X
X
X
X
X
Misalignment between pump
and driver
Re-align. Check coupling
alignment with dial indicator
X
X
X
X
Rotating elements binding
Disassemble and inspect
X
X
X
X
Pipe strain on pump casing
Disassemble pipe and re-
align before reassembling
X
X
Relief valve chattering
Check setting and valve
seating
X
X
X
X
Excessive system pressure
Check for obstructions in
discharge line.
X
X
X
Stuffing box packed too
tightly
Repack and adjust
X
Pump speed to low
Check pump impeller speed
X
X
Pump parts worn
Have pump reconditioned or
replace worn parts
X
X
Obstruction in discharge line Check discharge piping and
valves for obstruction
X
Wrong direction of rotation
Reverse motor
X
X
X
Suction line sized too small
Increase suction piping size
Torque control coupling not
adjusted
Readjust coupling