S SERIES PUMPS
OM-06111
MAINTENANCE AND REPAIR
PAGE E - 12
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 (13) and the impeller nut (12). 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 (14) 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 (11)
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 (10) and install it in
the suction head.
Position the suction head on the diffuser studs
(40). Using a soft faced mallet, “walk” the suction
head into the diffuser until fully seated. Be careful
not to damage the O‐ring (10). Apply `Never‐Seez'
or equivalent compound to the threads of the studs
(40) and secure the suction head using the nylon
locknuts (6). Torque the locknuts evenly in a cross
sequence to 60 ft. lbs. (720 in. lbs. or 8,3 m. kg.).
For maximum pump efficiency, there should be a
clearance of .010 to .015 inch (0,25 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 (15) as required. Install the impeller
and suction head and recheck impeller clearance.
NOTE
If the intermediate and rotor assembly (27 and 31)
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 (27) and the strainer plate (20) to ensure that
the old gasket and gasket cement is removed. In
spect the surface for major scratches. Secure the
strainer plate gasket (23) to the intermediate with a
light coating of `3M Gasket Adhesive No. 847' or
equivalent compound.
Position the strainer plate (20) over the diffuser,
aligning the bolt holes. Use a soft‐faced mallet to
tap the strainer plate into position.
Apply `Never‐Seez' or equivalent compound to the
threads of the capscrews (18). Install the hardware
(18, 35 and 36) and torque evenly in a cross se
quence to 120 ft. lbs. (1440 in. lbs. or 16,6 m. kg.).
Strainer Screen And Base Plate Installation
(Figure E-1)
Inspect the strainer screen (7) and base plate (8)
for cracks, distortion or erosion, and replace it if de
fective.
Carefully position the strainer screen on the strain
er plate (20) so that it seats against the strainer
plate shoulder. Install the base plate over the
screen, aligning the bolt holes. Secure the com
plete strainer assembly using the hardware (9, 35
and 36). Make certain that the strainer seats prop
erly against the shoulder of the strainer plate.
See
FINAL ASSEMBLY
and
VACUUM TESTING
followed by
LUBRICATION
before putting the
pump back into service.
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
tor be returned to Gorman‐Rupp, or to one of the
Gorman‐Rupp authorized Submersible Repair
