GHC SERIES
OM-05845
PAGE D-4
TROUBLESHOOTING
PREVENTIVE MAINTENANCE
Since pump applications are seldom identical, and
pump wear is directly affected by such things as
the abrasive qualities, pressure and temperature
of the liquid being pumped, this section is intended
only to provide general recommendations and
practices for preventive maintenance. Regardless
of the application however, following a routine pre
ventive maintenance schedule will help assure
trouble‐free performance and long life from your
Gorman‐Rupp rotary gear pump. For specific
questions concerning your application, contact
your Gorman‐Rupp distributor or the Gorman‐
Rupp Company.
Record keeping is an essential component of a
good preventive maintenance program. The ap
pearance of wearing parts should be documented
at each inspection for later comparison. Also, if re
cords indicate that a certain part (such as the seal)
fails at the same duty cycle, this part can be
checked and replaced before failure occurs.
Because of the tight tolerances within your rotary
gear pump, wear between rotating parts is normal
and expected. For new applications, a first inspec
tion at 250 hours will give insight into the wear rate
for your particular application. Subsequent inspec
tions should be performed at regular intervals of
2000 hours. Critical applications should be in
spected more frequently.
Check the thrust washer (medium duty models),
idler bushing, idler pin, idler assembly, shaft bush
ing and rotor/shaft assembly at each inspection.
Wear patterns should be uniform, without evi
dence of deep or irregular grooves.
For packing pumps, periodic adjustment of the
packing is required to keep leakage to a minimum
(see the adjustment procedure described under
Leakage
in
Operation, Section C
). Do not over
tighten. Replace the packing if leakage cannot be
reduced by a slight adjustment.
If the pump is equipped with a backhead bearing
(heavy duty models), inspect for free rotation of the
shaft and rotor, and excessive endplay or radial
movement of the shaft, which could indicate bear
ing wear. Remove the rotor adjusting sleeve as
sembly and inspect the bearing for damaged
seals. Replacing the bearing at the first indication
of a problem can extend the life of the pump and
save considerable expense later to replace major
components that can be damaged if the bearing is
allowed to fail.
After extended service, adjustment of the clear
ance between the rotor and the head will normally
improve performance (see the adjustment proce
dure in
Maintenance And Repair, Section E
).
If the pump is to be removed from service for repair,
be sure to protect the internal components from
rusting while the pump is disassembled and after
reassembly if not immediately placed back into
service.
