Gorman-Rupp Pumps 12B20-B 1340494 and up - Manual (Page 22)

TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
PUMP STOPS OR
FAILS TO DELIVER
RATED FLOW OR
PRESSURE (cont.)
PUMP REQUIRES
TOO MUCH
POWER
PUMP CLOGS
FREQUENTLY
Free impeller of debris. Impeller clogged.
Discharge head too low.
Dilute if possible. Liquid solution too thick.
Adjust discharge valve.
Open discharge valve fully to in­
crease flow rate, and run power
source at maximum governed
speed. Discharge flow too slow.
EXCESSIVE NOISE Cavitation in pump. Reduce suction lift and/or friction
losses in suction line. Record vac­
uum and pressure gauge readings
and consult local representative or
factory.
Secure mounting hardware. Pump or drive not securely mounted.
Locate and eliminate source of air
bubble. Pumping entrained air.
Suction check valve or foot valve
clogged or binding. Clean valve.
Suction lift or discharge head too high. Check piping installation and install
bypass line if needed. See INSTAL­
LATION.
Impeller clogged or damaged. Clean out debris; replace damaged
parts.
Leaking or worn seal or pump gasket. Check pump vacuum. Replace
leaking or worn seal or gasket.
Pump running backwards. Check direction of rotation and
correct by interchanging any two
motor leads at control box. (See
Pump Rotation, Section C).
Pump speed too slow. Check driver output; check belts
or couplings for slippage.
Pump speed too high. Check driver output check that
sheaves or couplings are correctly
sized.
BEARINGS RUN
TOO HOT Bearing temperature is high, but
within limits.
Align drive properly. Drive misaligned.
Check piping installation for proper
support. Suction and discharge lines not prop­
erly supported.
Check for proper type and level of
lubricant. Low or incorrect lubricant.
Check bearing temperature regular­
ly to monitor any increase.
OM-00588 10 SERIES
TROUBLESHOOTING PAGE D - 2