be cleaned and inspected before
position or it may be placed on a bench and wedged at
reassembly.
the sides for stability.
(1) Removal of the Commutator End Bearing.
g. Cleaning and Inspection of Armature Bearings.
The commutator end ball bearing is pulled
(1) Clean the bearings in gasoline also by
off as shown on figure 17. The procedure
means of dry, compressed air.
is as follows:
(2) Final cleaning will be in clean gasoline
(a) Remove the bolts which hold the
after which the bearings will be blown off
outside bearing cap to the bearing
with dry compressed air. Hold the cage or
cartridge and remove the cap.
inner race and rotate the outer race while
(b) Remove the two setscrews in the
directing the compressed air around the
bearing locknut and remove the
rollers, balls, cages or races. Next hold
locknut using the special wrench.
the outer race and rotate the cage or inner
race.
(c) Remove the bearing cartridge,
bearing, and oil thrower by applying
(3) If the bearing is not to be re-assembled
the puller as shown on the tool
immediately, grease and wrap in a
drawing.
protective covering to keep out dirt and
moisture.
(d) Wrap the bearing and grease
(4) In handling bearings during overhaul use
thrower in a protective covering,
clean lintless cloths for keeping both the
leaving the grease in the bearing.
hands and the bearings clean. I)o not use
The grease in the bearing will serve
waste on the bearings.
to prevent rusting. The bearing
must be cleaned and inspected
(5) Before re-assembling the bearings,
before reassembly in the housing.
carefully inspect for:
(2) Removal of the Pinion End Bearing. The
(a) Cracked races or cages.
pinion end roller bearing is removed as
(b) Cracked or pitted rollers or balls.
shown on the tool drawing, figure 17. The
(c) Excessive wear of cages or races.
procedure is as follows:
(d) Loose cage rivets.
(a) Remove the outer bearing stop
using the puller shown on figure 17.
(b) Remove the outer bearing cap.
have a perforated support approximately 2 inches above
(c) Remove the housing, bearing outer
the bottom to allow any dirt to drop below the bearings
race, and roller assembly.
and to prevent the heat front striking the bearings
(d) Remove the outer bearing race
directly. This container must be kept clean. Use a high-
from the housing, tap the housing
temperature oil such as compressor oil.
with a rawhide mallet and slip the
i. Assembly and Disassembly. If for any reason a
bearing out. If it is too tight in the
bearing inner or outer race does not pull readily from its
housing to be removed in the above
fit do not use a flame on the bearing. Instead pour hot
manner, the bearing can be tapped
oil over the inner race, lousing, or cartridge, to expand
out, using a brass bar on the outer
them enough to ease the fit and permit pulling.
race.
j. Removal and Replacing of Field Coils.
(e) Most of the work required on an
(1) In case one of the field coils has to be
armature can be done with the inner
remove, proceed as follows; (assuming
race in place. Be sure to thoroughly
motor frames have been dismounted and
clean the race, thrower, and cap
armature removed).
before assembly.
(a) Strip the insulation off the
(f) The inner race and cap may be
connections of the leads between
pulled when necessary, using the
the coil to be removed and the
puller shown on the tool drawing,
adjacent
coils,
unsolder
the
connections by the use of a
(g) Place the inner race in the bearing
blowtorch. Take care to protect the
and wrap in a protective covering
coil from the flame by pieces of
leaving the grease in the bearing.
asbestos sheet.
The grease in bearing will serve to
prevent rusting. The bearing must
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