OM-07089
S SERIES PUMPS
PAGE E - 15
MAINTENANCE AND REPAIR
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-6 for proper order of seal as
sembly.
Second Stage Impeller Installation
(Figure E-1)
Inspect the impeller (16) for cracks, broken vanes,
or wear from erosion, and replace it if damaged. In
spect the diffuser (23) and replace it if defective.
Clean the I.D. of the wear ring (5), and clean and oil
the impeller shaft and the I.D. of the impeller.
Install the impeller key (42) in the rotor shaft
keyway, align the impeller keyway, and press the
impeller onto the shaft until it is fully seated against
the shaft shoulder.
Be sure
the seal spring seats
squarely over the shoulder on the back of the im
peller.
Slide the impeller lockwasher (26) onto the shaft
until the inside tab on the lockwasher seats in the
milled slot on the shaft. Screw the impeller lock nut
(27) onto the shaft and tighten it with the lock nut
tool. When the lock nut is fully tight, back the nut off
to the nearest castellation, and bend two of the
tabs on the lockwasher up to lock the nut in place.
Second Stage Diffuser and Wear Ring
Installation
(Figure E-1)
If the wear ring (11) was removed from the second
stage diffuser (23), position the replacement ring in
the bore with the chamfer on the O.D. toward the
inside. Press the wear ring into the diffuser until ful
ly seated. Be sure the ring seats squarely in the dif
fuser bore.
NOTE
The wear ring
must
seat squarely in the diffuser;
otherwise, binding and/or excessive wear will oc
cur as the shaft turns.
Thoroughly clean the gasket surfaces, and the I.D.
of the wear ring (11). Install the gaskets (19 and
20), and position the diffuser against the intermedi
ate (47). Apply `Never‐Seez' or equivalent com
pound to the threads of the capscrews and studs
(25 and 34), and secure the diffuser to the interme
diate by torquing the hardware evenly in a cross
sequence to 300 ft. lbs. (3600 in. lbs. or 41,5 m.
kg.).
First Stage Diffuser and Vane Plate Installation
(Figure E-1)
If the wear ring (5) was removed from the vane
plate (9), position the replacement ring in the bore
from the back side and align the holes for the caps
crews (29). Press the wear ring into the vane plate
until fully seated. Be sure the ring seats squarely in
the vane plate bore.
NOTE
The wear ring
must
seat squarely in the vane plate;
otherwise, binding and/or excessive wear will oc
cur as the shaft turns.
Secure the wear ring in the vane plate with the
hardware (12 and 13).
Secure the vane plate to the first stage diffuser (8)
with the socket head capscrews (25). Install the
gasket (24) and position the first stage diffuser
against the second stage diffuser. Apply `Never‐
Seez' or equivalent compound to the capscrews
(25), install the hardware (14, 15 and 25), torquing
the capscrews evenly in a cross sequence to 120 ft.
lbs. (1440 in. lbs. or 16,6 m. kg.).
First Stage Impeller Installation
(Figure E-1)
Inspect the first stage impeller (7) for cracks, bro
ken 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 completely dry.
Push the impeller onto the shaft until seated firmly
against the shaft shoulder. Install the impeller
washer (26) on the rotor shaft (40).
NOTE
If the impeller is not fully seated and binds against
