SB--7--626 Page 17
FIGURE 15 -- BEARING CARTRIDGE REMOVAL
BEARING
RETAINING
RING *
BEARING
BEARING
CARTRIDGE
O--RING
D
C
B
A
* Later models use (4) clips instead of solid ring.
BEARING AND SEAL REPLACEMENT
Gear End
Remove the gear case (see “Gear Inspection,” page
14). Note the end clearance between the impeller and
gear headplate. Remove the timing gears as instructed
previously.
Refer to FIGURE 15.
Shims (A) installed during
manufacture will now be exposed behind the bearing
cartridge (B). These shims set the end clearance
between the impeller and headplate; therefore, it is
important that they be returned to their exact positions
on reassembly.
(NOTE:
The number of shims
fastened behind each bearing cartridge bolt may vary;
be sure each set of shims is identified by position during
withdrawal). To remove the shims, remove the bearing
cartridge bolts (C). Insert jack screws in tapped holes
(D) provided in the cartridge and back out the cartridge
until the shims are loose. Remove one attachment bolt
at a time, taking out the shims and marking them for
accurate repositioning.
On removal of all bolts,
continue using the jackscrews to complete the
cartridge removal. Remove the bearing retainer ring
(or clips), from the face of the cartridge.
Blowers have a lip type oil seal behind each bearing.
Gas pumps have a mechanical seal.
Lip Type Oil Seal
Whenever a cartridge is removed for repair purposes,
always install a new seal and O--ring before
FIGURE 16 -- MECHANICAL SEAL
reassembly. Install the seal with the lip facing the bear-
ing, using a driving instrument having approximately
the same outside diameter as the seal. Use caution not
to damage the sealing elements, particularly when they
are moved over the shaft.
Mechanical Seal
Refer to FIGURE 16. When replacing, remove the oil
seal components. Clean the shaft carefully, especially
under the O--ring inserted in the groove of the mating
ring, item 45. Before sliding item 45 into position, be
sure to break the sharp edges at the shaft diameter