Xylem IM191 R03 Marlow Series Prime Line Self-Priming Centrifugal Pumps User Manual
Page 10

10
WARNING
Hazardous voltage
can shock, burn or
cause death.
Troubleshooting
DISCONNECT
AND
LOCKOUT
ELECTRICAL
POWER
BEFORE
ATTEMPTING
ANY
MAINTENANCE.
FAILURE TO DO SO CAN CAUSE A
SHOCK, BURN OR DEATH.
NOTE: Before implementing any remedial action recommended in the following Troubleshooting guide, refer to
“Recommended Precautions” and “Warning” sections of this manual. The following are some common causes of
problems that may arise.
Symptoms
Probable Cause
Recommended Action
Will not prime
No liquid in pump casing (1).
Fill pump casing with liquid being
pumped.
Loose suction inlet (50).
Tighten bolts.
Worn suction inlet gasket (49).
Replace with new gaskets.
Loose drain plug (2).
Tighten plug, use pipe dope or
Teflon tape.
Worn pump shaft seal assembly (17).
Install new seal.
Leaky suction line.
Fix leaky suction. Check all
gasketed surface.
Worn diffuser gasket (7).
Replace diffuser gasket.
Suddenly stops pumping.
Clogged suction line or suction
Clean suction line and strainer
strainer (if used).
Stops pumping until motor is
Collapsing suction hose lining.
Replace suction line and strainer.
stopped and restarted.
Slowly stops pumping.
Clogged impeller (6) or (91),
Clean out debris from impeller eye
diffuser (46), check valve (51) or
area, suction check valve, or from
suction line.
diffuser vanes.
Excessive leakage around shaft.
Work pump shaft seal (17).
Replace seal assembly.
Will not hold prime.
Dislodged or worn check valve (51).
Clean or replace check valve. Clean
sealing surface.
Small leak in suction line.
Check suction hose or piping for
leak.
Worn seal or packing.
Replace seal or packing.
Poor performance
Impeller (6) or (91), seal
Install new impeller, seal or diffuser.
assembly (17) or diffuser (46).
Motor not up to speed:
(a) larger lead wires required
(a) low voltage (b) worn bearings
(b) replace bearings.
Noisy operation
Worn motor bearings.
Replace.
Low discharge head.
Throttle discharge.
Impeller clogged.
Remove and clean impeller.
Worn coupling or misalignment.
Replace or realign coupling.
Units operating at extreme left or
Adjust for best performance point
right end of performance curve
of operation.
(capacity too high or too low).
Bearings running dry.
Check oil level or grease –
add if required.