Gorman-Rupp Pumps SFV3B 1473390 and up - Manual (Page 38)

OM-06400 SF SERIES
PAGE E - 11 MAINTENANCE AND REPAIR
NOTE
If the seal plate was not removed during disassem­
bly, cover the stationary element with a clean tissue
and use your thumbs to press the seal stationary
seat and element into the seal plate as described
above. Remove the tissue and inspect the seal face
to ensure that it is clean and dry.
Unpack the rotating portion of the seal. Be certain
the seal face of the rotating element is free of grit or
surface damage. Because the rotating element
may not stay in the bellows retainer when turned
upside down, place a small amount of grease at
equal spaces on the back of the element and posi­
tion it in the bellows retainer. The grease should
hold the element in position until the seal is in­
stalled. Assemble the drive grooves of the rotating
element into the drive lugs of the bellows retainer.
Apply a light coating of oil on the shaft and the I.D.
of the bellows.
NOTE
When pressing seal components onto the rotor
shaft, use hand pressure only. A push tube cut from
a length of plastic pipe will aid in installing seal
components. The I.D. of the push tube should be
approximately the same as the I.D. of the seal
spring.
Slide the seal rotating portion onto the lubricated
shaft with the seal face down. Apply firm, steady
pressure on the bellows retainer until it slides down
the shaft and the seal faces contact.
Install the seal spring over the bellows retainer and
install the spring retainer (18). See Figure E-3 for
proper order of seal assembly.
Impeller Installation
(Figure E-1)
Inspect the impeller (2) for cracks, broken vanes,
or wear from erosion and replace it if damaged.
Clean the threads in hole in the rotor shaft for the
impeller screw (4).
Install the same thickness of adjusting shims (19)
as previously removed. Install the impeller key (16,
Figure E-2) in the rotor shaft keyway. Align the
keyway of the impeller (2) with the shaft key and
push the impeller onto the shaft until seated firmly
against the upper impeller shim set.
A clearance of .020 to .040 inch (0,51 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 rotor/shaft (or impeller screw, if so equipped)
with `Loctite Threadlocker No. 242' or equivalent
compound. Install the impeller washer (3). Wedge
a soft metal bar between the vanes of the impeller
or use a strap wrench to prevent shaft rotation.
Torque the impeller nut (4) to 78 ft. lbs. (10,8 m.
kg.). If so equipped, torque the impeller screw to
5.6 ft. lbs. (67 in. lbs. or 7,6 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 E-1)
Install a new O‐ring (15) on the shoulder of the seal
plate. Orient the pump casing (1) as shown in Fig­
ure E-1 and slide it over the seal plate shoulder
until fully seated. Apply “Never‐Seez” or equivalent
compound to the capscrews (9) and secure the
pump casing to the seal plate and motor assembly
(7) with the hardware (8 and 9). Torque the caps­
crews to 27 ft. lbs. (327 in. lbs. or 3,8 m. kg.).
Final Assembly
If the pump guide shoe was removed for disassem­
bly, install a new guide shoe seal and secure the
seal and guide shoe to the pump casing with the
previously removed hardware.
Use a suitable lifting device to reposition the pump
in the wet well or sump.
MOTOR DISASSEMBLY
Disassembly of the motor is rarely required except
to replace the motor rotor, stator or bearings. Do
not disassemble the motor unless it is necessary
and a clean, well‐equipped shop is available.
NOTE
It is recommended that a pump with a defective mo­