Gorman-Rupp Pumps 81 1/2A2-B 253703 and up User Manual
Page 26
OM−00740
80 SERIES
MAINTENANCE & REPAIR
PAGE E − 5
wise until it rests against the cover (see Figure 4) to
prevent the grease in the cup from escaping. Re-
move the grease cup and piping (7, 8 and 9).
Immobilize the impeller by wedging a block wood
between the vanes. If removed, install the shaft
key (16). Install a lathe dog on the drive end of the
shaft (17) 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 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 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 (10)
off the impeller shaft. Tie and tag the shims, or
measure and record their thickness for ease of
reassembly.
Seal Removal and Disassembly
Remove the outer rotating element. Slide the seal
plate, shaft sleeve, and remaining seal parts off the
shaft as a unit. Carefully remove the stationary and
rotating seal elements, packing rings and wash-
ers, seal spring and shaft sleeve from the seal
plate.
NOTE
The seal assembly may be removed without com-
pletely disassembling the pump by removing the
impeller through the back cover opening and using
a pair of stiff wires with hooked ends to pull the seal
parts out of the seal plate.
Inspect the seal plate and replace it if cracked or
badly worn. Inspect the seal liner (11) for wear or
grooves that could cause leakage or damage to
the seal packing rings. The seal liner is a press fit
into the seal plate and does not normally require re-
placement. If replacement is required, see Seal
Installation.
Shaft And Bearing Removal And Disassembly
When the pump is properly operated and main-
tained, the pedestal should not require disassem-
bly. Disassemble the shaft and bearings only
when there is evidence of wear or damage.
Shaft and bearing disassembly in the field
is not recommended. These operations
should be performed only in a properly
equipped shop by qualified personnel.
NOTE
There are no provisions for draining the grease
from the pedestal. Place a drip pan under the ped-
estal before removing the shaft and bearings.