| TROUBLE |
TYPE
OF PUMP |
LOOK
FOR |
| |
VARIABLE
HEAD |
BYPASS
HEAD |
SOLID
HEAD |
| • |
• |
• |
CW
PUMP RUNNING CCW. OR VICE VERSA
MOTOR WIRING REVERSED
PIPING TO WRONG PORTS |
| • |
• |
• |
DISCHARGE
HEAD TOO HIGH
PIPING TOO SMALL, TOO LONG
VISCOSITY TOO HIGH |
| • |
|
|
FLOW
CONTROL TURNED DOWN TO ZERO |
| • |
|
|
PAWL
PIN MISSING
CONTROL SPRING- not adjusted - wound
backwards - distorted - broken out
of top or bottom spring plate |
| |
• |
|
RELIEF
VALVE SPRING - not adjusted - not
in correct position - spring broken |
| • |
|
|
PLUNGER
FROZEN IN BOTTOM POSITION - corroded
parts - pumpage shear sensitive
- dirt accumulation preventing movement |
| |
• |
|
RELIEF
VALVE - not fully seated - stuck
on valve guide pin - need lapping
into seat - spring adjusting plate
missing |
| • |
• |
• |
INADEQUATE
PRIMING CONDITIONS SUCH AS - suction
line air leak - foot valve stuck
- lift too great - altitude too
high - vapor lock |
| • |
• |
• |
ROTOR
GROUP WORN / MECHANICAL SEAL WORN
OR BROKEN |
| CAVITATING
VIBRATING
HIGH AMP. DRAIN |
• |
• |
• |
STARVED
SUCTION LINE DUE TO - suction line
restricted - viscosity too great
for piping - RPM too high for viscosity |
PUMP
RUNNING
HOT |
• |
• |
• |
PACKING
TOO TIGHT
MISALIGNMENT
OBSTRUCTION IN ROTOR GROUP
RUSTED PARTS- blush rust causing
parts to seize together |
| • |
• |
|
TOO
LONG RUNNING IN FULL BYPASS CYCLE
OR ZERO STROKE |
| • |
• |
• |
OVERSPEEDING
CAVITATION |
|
PUMP
FROZEN
CAN'T TURN
SHAFT |
• |
• |
• |
PACKING
TOO TIGHT
MISALIGNED PUMP
INSUFFICIENT LUBRICATION OF SHAFT |
| • |
• |
• |
PUMPAGE
- shear sensitive - congealed -
caramelized - solidified
TEMPERATURE OF ALL BRONZE OR BRONZE
FITTED PUMP EXCEEDING 140°F
ROTOR GROUP NOT RELIEVED |
NOISY
PUMP |
• |
• |
• |
CAVITATION
WORN ROTOR GROUP
AIR LEAK INTO SUCTION LINE |
| • |
• |
|
PLUNGER
OR VALVE BOUNCING DUE TO-
suction line restriction - relief
valve in discharge line reacting
with pump spring setting - PIPING
RESONANCE |
EXCESSIVE
LEAKAGE FROM
PACKING GLAND |
• |
• |
• |
PACKING
NUTS INCORRECTLY ADJUSTED
PACKING WORN
MECHANICAL SHAFT SEAL WORN OR BROKEN
SHAFT SCORED |
REDUCTION
OF FLOW
OR PRESSURE |
• |
|
|
PAWL
PIN BROKEN
CONTROL SPRING SETTING INCORRECT
CONTROL PLUNGER STUCK |
| |
• |
|
BYPASS
SPRING SETTING INCORRECT
VALVE UNSEATED OR WORN |
| • |
• |
• |
PUMP
WORN
RESTRICTION OR TOO HIGH VISCOSITY
IN SUCTION LINE |
| PREMATURE
WEAR
SHORT
PUMP
LIFE |
• |
• |
• |
MISALIGNMENT
- end or side thrust on shaft
PACKING TOO TIGHT OR ADJUSTED INCORRECTLY
DIRTY OR ABRASIVE PUMPAGE
RUNNING PUMP DRY - repeated suction
lift
OVERSPEEDING
NON-LUBRICATING PUMPAGE OPERATING
ABOVE 50 PSI & 350 RPM |
| • |
|
|
FLOW
CONTROL LINE SET BELOW 25% CAPACITY
FOR TOO LONG PERIODS
SUCTION LINE RESTRICTED CAUSING
PLUNGER TO “BOUNCE” |
SCORED
OR
GOUGED PARTS |
• |
• |
• |
MISALIGNMENT
- transmittal of end thrust from
motor shaft - excessive belt tension
- PIPE STRAIN - OVER TIGHTENING
OF GLAND |
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