Gorman-Rupp Pumps S4A1-E25 460/3 1396155 and up - Manual (Page 37)

OM-06098 S SERIES PUMPS
PAGE E - 11 MAINTENANCE AND REPAIR
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.
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.
Slide the seal spring over the shaft and bellows re­
tainer. See Figure E-3 for proper order of seal as­
sembly.
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 on the rotor shaft to remove any
old thread locking material. Be sure the impeller
bore and the shaft are free of oily film and com­
pletely dry.
Install the upper impeller washer (35) with the in­
side chamfer toward the shaft shoulder. Install the
adjusting shims (36) and the impeller key (65).
Align the keyway of the impeller (2) and push the
impeller onto the shaft until seated firmly against
the upper impeller washer and shim set.
After the impeller is installed, coat the threads of
the rotor shaft with `Loctite Threadlocker No. 242'
or equivalent compound. Install the impeller wash­
er (63) and the impeller nut (64). Wedge a block of
wood between the vanes of the impeller and torque
the nut to 175 ft. lbs. (2100 in. lbs. or 24,2 m. kg.).
Remove the block of wood and turn the impeller to
check for free rotation.
NOTE
If the impeller (2) is not fully seated and binds
against the diffuser, the shaft and lower bearing
have been driven out of position during impeller re­
moval. If this occurs, the lower bearing must be
pressed back into place (see MOTOR DISASSEM­
BLY and MOTOR REASSEMBLY).
Suction Head And Strainer Plate Installation
(Figure E-1)
Inspect and thoroughly clean the suction head (62)
and its O‐ring groove. It must be clean and free of
any flaws which could cut the O‐ring or prevent a
good seal. Lightly oil the O‐ring (54) and install it in
the suction head.
Position the suction head on the diffuser studs
(60). Using a soft faced mallet, “walk” the suction
head into the diffuser until fully seated. Be careful
not to damage the O‐ring (54). Apply `Never‐Seez'
or equivalent compound to the threads of the studs
(60) and secure the suction head using the nylon
locknuts (61). Torque the locknuts evenly in a cross
sequence to 20 ft. lbs. (240 in. lbs. or 2,8 m. kg.).
For maximum pump efficiency, there should be a
clearance of .008 to .015 inch (0,20 to 0,38 mm) be­
tween the suction head and the face of the impeller.
Use a feeler gauge to measure this clearance. If the
clearance is not within the specific limits, remove
the suction head and impeller. Add or remove ad­
justing shims (36) as required. Install the impeller
and suction head and recheck impeller clearance.
NOTE
If the intermediate and rotor assembly (51 and 40)
were not removed from the motor housing during
pump end disassembly, allowance must be made
for bearing play when checking impeller clearance.
Final impeller clearance must be determined with
the pump in a normal upright operating position.
Clean the gasket surface between the intermedi­
ate (51) and the strainer plate (53) to ensure that
the old gasket and gasket cement is removed. In­
spect the surface for major scratches. Secure the
strainer plate gasket (52) to the intermediate with a
light coating of `3M Gasket Adhesive No. 847' or
equivalent compound.
Position the strainer plate (53) over the diffuser,
aligning the bolt holes. Use a soft faced mallet to
tap the strainer plate into position.