Gorman-Rupp Pumps PA4A60-4024T 1476457 and up - Manual (Page 39)

OM−06415 PA SERIES
MAINTENANCE & REPAIR PAGE E − 17
Position a clean container under the seal cavity
drain plugs (8, Figure 4 and 24A, Figure 5). Re-
move the plugs and drain the oil from the seal cav-
ity into the container. For shorter drain time, re-
move the vented plug (8, Figure 5). Clean and rein-
stall the drain plugs and vent plug. Inspect the oil
for water, dirt or a cloudy condition which could in-
dicate seal failure.
Loosening Impeller
(Figure 5)
With the pump end separated from the engine,
wedge a block of wood between the vanes of the
impeller (1) and the pump casing (1, Figure 4) to
prevent rotation.
Install the shaft key (23) in the shaft keyway. Install
a lathe dog on the drive end of the shaft (20) with
the V" notch positioned over the shaft key.
With the impeller rotation still blocked, see Figure 9
and use a long piece of heavy bar stock to pry
against the arm of the lathe dog in a counterclock-
wise direction (when facing the drive end of the
shaft). Use caution not to damage the shaft or key-
way. When the impeller breaks loose, remove the
lathe dog, key and wood block.
Turn
Counterclockwise
Lathe Dog Arm
V" Notch
Shaft Key
Impeller Shaft
Lathe Dog
Setscrew
Heavy
Bar Stock
Figure 9. Loosening Impeller
Pump Casing And Wear Plate Removal
(Figure 4)
Support the pump casing using a suitable hoist
and sling.
Use lifting and moving equipment in
good repair and with adequate capacity
to prevent injuries to personnel or dam-
age to equipment. If slings or chains are
used to move the pump or components,
make sure that the load is balanced;
otherwise serious personal injury or
death could result. Suction and dis-
charge hoses and piping must be re-
moved from the pump before lifting.
NOTE
Drain the oil from the seal cavity before removing
the pump casing. See Draining Oil From Seal Cav-
ity.
Remove the hardware (6 and 7) securing the pump
casing (1) to the rotating assembly (5). Pull the
pump casing straight away from the rotating as-
sembly to prevent binding on the impeller. Remove
the shims (8). Tie and tag the shims or measure
and record their thickness for ease of reassembly.
Inspect the wear plate assembly (2) for excessive
wear or scoring. If replacement is required, remove
the hardware (11 and 12) and pull the wear plate
out of the pump casing.
Impeller Removal
(Figure 5)
With the rotating assembly removed from the
pump casing, unscrew the impeller (1) from the
shaft (20). Use caution when unscrewing the im-
peller; tension on the shaft seal spring will be re-
leased as the impeller is removed. Inspect the im-
peller and replace if cracked or badly worn.
Remove the impeller adjusting shims (25); tie and
tag the shims, or measure and record their thick-
ness for ease of reassembly.