Gorman-Rupp Pumps 81 1/2A52-B 1233759 and up - Manual (Page 18)

OM−00789 80 SERIES
TROUBLESHOOTING PAGE D − 2
TROUBLE POSSIBLE CAUSE PROBABLE REMEDY
PUMP STOPS OR
FAILS TO DELIVER
RATED FLOW OR
PRESSURE (cont.)
PUMP REQUIRES
TOO MUCH
POWER
PUMP
CLOGS FRE-
QUENTLY
Impeller or other wearing parts worn
or damaged. Replace worn or damaged parts.
Check that impeller is properly
centered and rotates freely.
Impeller clogged. Free impeller of debris.
Pump speed too slow. Check driver output; check belts
or couplings for slippage.
Discharge head too high. Install bypass line.
Suction lift too high. Measure lift w/vacuum gauge. Re-
duce lift and/or friction losses in
suction line.
Pump speed too high. Check driver output; check that
sheaves or couplings are cor-
rectly sized.
Discharge head too low. Adjust discharge valve.
Liquid solution too thick. Dilute if possible.
Bearing(s) frozen. Disassemble pump and check
bearing(s).
Liquid solution too thick. Dilute if possible.
Discharge flow too slow. Open discharge valve fully to in-
crease flow rate, and run power
source at maximum governed
speed.
Suction check valve or foot valve
clogged or binding. Clean valve.
EXCESSIVE NOISE Cavitation in pump.
Impeller clogged or damaged.
Pump or drive not securely mounted.
Pumping entrained air.
Reduce suction lift and/or friction
losses in suction line. Record vac-
uum and pressure gauge readings
and consult local representative or
factory.
Locate and eliminate source of air
bubble.
Secure mounting hardware.
Clean out debris; replace dam-
aged parts.
BEARINGS
RUN TOO HOT Bearing temperature is high, but
within limits. Check bearing temperature regu-
larly to monitor any increase.
Low or incorrect lubricant. Check for proper type and level of
lubricant.
Suction and discharge lines not
properly supported. Check piping installation for
proper support.
Drive misaligned. Align drive properly.