Gorman-Rupp Pumps 12B65-B 776101 and up - Manual (Page 28)

OM-02149 10 SERIES
MAINTENANCE & REPAIR PAGE E - 5
Pump Casing Removal
Death or serious personal injury and
damage to the pump or components
can occur if proper lifting procedures
are not observed. Make certain that
hoists, chains, slings or cables are in
good working condition and of suffi­
cient capacity and that they are posi­
tioned so that loads will be balanced
and the pump or components will not be
damaged when lifting. Suction and dis­
charge hoses and piping must be re­
moved from the pump before lifting. Lift
the pump or component only as high as
necessary and keep personnel away
from suspended objects.
To service the impeller or seal assembly, discon­
nect the discharge piping. Remove the hardware
securing the pump to the base.
Remove the nuts (34) and separate the pump cas­
ing and gasket set (36) from the seal plate (35) and
pedestal (25). Tie and tag any leveling shims used
under the pump mounting feet to ease reassembly.
Remove the gasket set. Tie and tag the gaskets, or
measure and record their thickness for ease of
reassembly. Clean the mating surfaces of the seal
plate and pump casing.
Impeller Removal
Disconnect the power source.
Immobilize the impeller by wedging a block of
wood between the vanes. If removed, install the
shaft key (20). 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 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 in a counterclockwise direc­
tion.
Inspect the impeller and replace it if cracked or
badly worn. Slide the impeller adjusting shims (9)
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
Slide the shaft sleeve (12) and rotating portion of
the seal off the shaft as a single unit. Measure and
record the distance from the impeller end of the
sleeve to the end of the seal retainer, or use a felt‐tip
marker to scribe a line on the sleeve at this location.
Loosen the setscrews securing the retainer to the
sleeve and slide the rotating portion of the seal off
the sleeve.
Slide the seal plate and stationary seal compo­
nents off the shaft as a single unit. Place the seal
plate on a flat surface with the impeller side down.
Remove the nuts (32) and separate the seal clamp
(11) and stationary portion of the seal from the seal
plate. Remove the stationary portion of the seal
from the seal clamp.
If no further disassembly is required, see Seal
Reassembly and Installation.