Gorman-Rupp Pumps PAV3B60C-3TNV70 1433753 and up - Manual (Page 38)

PA SERIES OM-06260
MAINTENANCE & REPAIR PAGE E - 20
Carefully wash all metallic parts in fresh cleaning
solvent and allow to dry thoroughly.
Do not attempt to separate the rotating
portion of the seal from the shaft sleeve
when reusing an old seal. The rubber bel­
lows will adhere to the sleeve during use,
and attempting to separate them could
damage the bellows.
Inspect the seal components for wear, scoring,
grooves, and other damage that might cause leak­
age. Inspect the integral shaft sleeve for nicks or
cuts on either end. If any components are worn, or
the sleeve is damaged, replace the complete seal;
never mix old and new seal parts.
Install the stationary seal element in the stationary
seat. Press this stationary subassembly into the
seal plate bore until it seats squarely against the
bore shoulder. A push tube made from a piece of
plastic pipe would aid this installation. The I.D. of
the pipe should be slightly larger than the O.D. of
the shaft sleeve.
Slide the rotating portion of the seal (consisting of
the integral shaft sleeve, spring centering washer,
spring, bellows and retainer, and rotating element)
onto the shaft until the seal faces contact.
Proceed with Impeller Installation and Adjust­
ment.
Impeller Installation and Adjustment
(Figure 2)
Inspect the impeller (1) for cracks, broken vanes,
or wear from erosion and replace it if damaged.
Clean the threads in hole in the impeller shaft for
the impeller screw (33).
Install the same thickness of adjusting shims (3) as
previously removed. Install the impeller key (31) in
the shaft keyway. Align the keyway of the impeller
with the shaft key and push the impeller onto the
shaft until seated firmly against the impeller shim
set.
A clearance of .025 to .040 inch (0,63 to 1,02 mm)
between the impeller and the seal plate is recom­
mended for maximum pump efficiency. Measure
this clearance and add or remove impeller adjust­
ing shims as required.
After the impeller is installed, coat the threads of
the impeller screw with `Never‐Seeze' or equivalent
compound. Install the impeller washer (34).
Wedge a soft metal bar between the vanes of the
impeller or use a strap wrench to prevent shaft rota­
tion. Torque the impeller screw to 90 ft. lbs. (12,4 m.
kg.).
Remove the metal bar or strap wrench used to pre­
vent shaft rotation and turn the impeller to check for
free rotation.
Pump Casing Installation
(Figure 2)
Lubricate the O‐ring (36) with light grease and in­
stall it over the shoulder on the seal plate (5, Figure
2). Use a suitable lifting device to position the
pump casing against the seal plate. Be careful not
to damage the O‐ring.
Secure the pump casing to the rotating assembly
with the hardware (34 and 35).
If the suction spool (7) was removed, replace the
gasket (4) and position the spool against the pump
casing. See Figure 1, reinstall the pump support
bracket (26) and secure it to the base with the pre­
viously removed hardware (27, 28, 29 and 30). Se­
cure the spool to the pump with the hardware (5
and 7).
Flap Valve Installation
(Figure 2)
Inspect components of the check valve assembly
(18) and replace as required. If separated at disas­
sembly, press the spacer sleeves through the flap
valve. Install the backup plate and flap valve ad­
aptor and secure the components with the previ­
ously removed nylock capscrews.
If the gasket (4) was removed, clean the mating
surfaces of the casing (1) and flange (15). Install
the new gasket and the flange against the pump
casing.