Gorman-Rupp Pumps PA12A60-B-6068H 1435345 and up - Manual (Page 40)

PA SERIES OM-06296
MAINTENANCE & REPAIR PAGE E - 20
NOTE
When removing the pump casing, use a wire to se­
cure the assembled bottle oiler (54, Figure 6) and
bracket (12, Figure 6) above the level of the oil in the
seal cavity. This will prevent oil from leaking out of
the oiler during disassembly.
If the impeller (2) is to be removed, the impeller
screw (7) should be loosened before removing the
pump casing. Immobilize the impeller by inserting
a wood block through the pump discharge and
into the impeller vanes. Remove the impeller screw
and washer (8). Remove the wood block from the
pump discharge.
Remove the hardware (13, 14 and 15, Figure 6) se­
curing the pump casing and bottle oiler bracket to
the pedestal (20, Figure 6).
Pull the pump casing straight away from the ped­
estal to prevent binding on the impeller. Remove
the casing gasket (6) and clean the contacting sur­
faces.
Impeller Removal
(Figure 5)
Before removing the impeller, loosen the hose
clamp (10, Figure 6) and remove the hose (48, Fig­
ure 6) from the lower connector (11, Figure 6). Re­
move the bottle oiler and bracket assembly and
drain the seal cavity. This will prevent the oil in the
oiler from escaping when the impeller is removed.
With the impeller screw and washer removed as
described in Pump Casing Removal, insert a pair
of wedges 180
_ apart between the impeller and the
seal plate (40, Figure 6). Tap the wedges alternate­
ly to force the impeller off the shaft. Retain the im­
peller key (33, Figure 6).
Inspect the impeller wear ring for excessive wear or
scoring.
Proper replacement of the impeller wear
ring requires machining and dynamic bal­
ancing the impeller assembly after the new
wear ring is welded to the impeller. Failure
to properly install the new wear ring and
machine and balance the impeller assem­
bly can result in premature shaft, seal or
bearing failure, or other damage to the
pump.
To replace the wear ring, grind off the three weld
spots securing the wear ring to the impeller. Use
caution not to damage the impeller. Pry or carefully
grind the wear ring off the impeller.
Seal Removal
(Figures 5 and 12)
This pump is designed with two seals; a primary
mechanical seal (3) located directly behind the im­
peller and a secondary oil seal (23, Figure 6) lo­
cated in the seal plate cover (45, Figure 6). If the liq­
uid being pumped leaks past the oil seal, both
seals should be replaced immediately.
Remove the impeller shims (42). Tie and tag the
shims for ease of reassembly. Remove the seal
spring. Slide the rotating portion of the seal (con­
sisting of the shaft sleeve and O‐ring, bellows and
retainer, and rotating element) off the shaft as a
unit.
Apply oil to the sleeve and work it up under the rub­
ber bellows. Slide the bellows and retainer off the
sleeve. Remove the sleeve O‐ring.
Slide the seal plate and remaining seal compo­
nents off the shaft. Disengage the hardware (46
and 47, Figure 6) and separate the seal plate cover
and O‐ring (37, Figure 6) from the seal plate.
Use a suitably sized dowel to press the stationary
portion of the seal out of the seal plate. Press the oil
seal out of the seal plate cover.
If no further disassembly is required, refer to Seal
Installation.
Pedestal Assembly Removal
(Figure 2)
Disassembly of the pedestal requires separation of
the pump and driver. Disengage the hardware se­
curing the belt guard to the lifting bail and remove
the guard.
Loosen, but do not remove, the hardware securing
the pump suction head (49, Figure 5) and pedestal
(20, Figure 6) to the fuel tank assembly (19).