Gorman-Rupp Pumps 13C20-B 710764 and up - Manual (Page 29)

OM-00641 10 SERIES
MAINTENANCE & REPAIR PAGE E - 5
Inspect the wear plate and replace it if badly scored
or worn. To remove the wear plate, disengage the
hardware (48 and 49) securing it to the back cover.
If no further disassembly is required, see Back
Cover Installation.
Suction Check Valve Removal
and Disassembly
If the check valve assembly (53) is to be serviced,
remove the check valve pin (60), reach through the
back cover opening and pull the complete assem­
bly from the suction flange (52).
Inspect the check valve parts for wear or damage.
If replacement is required, remove the nylock
capscrews (54) and separate the check valve (57)
from the adaptor (58) and backup plate (55). Press
the spacer sleeves (56) out of the check valve.
If no further disassembly is required, see Suction
Check Valve Installation.
Pump Casing Removal
To service the impeller or seal assembly, discon­
nect the discharge piping. Remove the hardware
securing the pump to the base. Disconnect the
power source.
Remove the nuts (34) and separate the pump cas­
ing and gasket set (36) from the seal plate (35) and
pedestal (15). Clean the mating surfaces of the
seal plate and pump casing. Tie and tag the casing
gaskets, or measure and record their thickness for
ease of reassembly.
Tie and tag any leveling shims used under the
pump casing mounting feet to ease reassembly.
Impeller Removal
Before removing the impeller, remove the bottle oil­
er and piping (8, 9 and 10). Remove the seal cavity
drain plug (32) and drain the cavity to prevent the
oil from escaping when the impeller is removed.
Clean and reinstall the drain plug.
Immobilize the impeller by wedging a block wood
between the vanes. If removed, install the shaft key
(21). Install a lathe dog on the drive end of the shaft
(22) with the “V” notch positioned over the shaft
keyway.
With the impeller rotation still blocked, strike the
lathe dog sharply in a counterclockwise direction
(when facing the drive end of the shaft). The impel­
ler may also be loosened by using a long piece of
heavy bar stock to pry against the arm of the lathe
dog in a counterclockwise direction (when facing
the drive end of the shaft) as shown in Figure E-2.
Use caution not to damage the shaft or keyway.
When the impeller breaks loose, remove the lathe
dog and wood block and unscrew the impeller
from the shaft.
Turn
Counterclockwise
Lathe Dog Arm
“V” Notch
Shaft Key
Impeller Shaft
Lathe Dog
Setscrew
Heavy
Bar Stock
Figure E-2. Loosening Impeller
Unscrew the impeller from the shaft. Use caution
when removing the impeller; tension on the seal
spring will be released as the impeller is un­
screwed.
Inspect the impeller and replace it if cracked or
badly worn. Slide the impeller adjusting shims (11)
off the impeller shaft. Tie and tag the shims or mea­
sure and record their thickness for ease of reas­
sembly.
Seal Removal and Disassembly
Remove the spring centering washer and seal
spring. Slide the shaft sleeve (13) and rotating por­
tion of the seal off the shaft as a single unit. Apply oil
to the sleeve and work it up under the bellows.
Slide the rotating portion of the seal off the sleeve.
Slide the seal plate and stationary portion of the
seal assembly off the shaft as a unit. Position the
seal plate on a flat surface with the impeller side
down. Use a suitably sized dowel to press the seal
stationary components from the seal plate bore.
Position the seal plate on a flat surface with the im­
peller side up and press the oil seal (12) from the
seal plate.