commutator and secure with friction tape.
(6) Remove the inner race from the hot oil,
wipe off the excess oil and apply to the
This serves to protect the commutator
from the brushholders when dropping the
shaft using the bucking-up tool as before.
armature in place.
(7) Fill the spaces between the rollers in the
Screw the two armature removal studs
bearing and fill the grease chamber in the
into the commutator end cartridge to be
caps about one half full with grease as
used as a guide in lining up the holes in
the cartridge with those ill the frame.
(8) Tap the bearing in place in the housing
Pick up the armature, using the special
using the outer bearing cap to determine
armature lifting eye, and lower into the
frame, being careful not to score the
(9) Slide the housing and outer race and
commutator or the bearing and to get the
roller assembly into place, being careful
studs entered in the proper housing holes.
not to score the inner race with the rollers.
Put the pinion end housing bolts in place.
(10) Check the internal radial clearance of the
Remove the studs from the commutator
See the bearing assembly
end cartridge and put in the proper bolts.
Pull the commutator end cartridge fit and
(11) Apply the outer bearing cap and bolt in
the pinion end housing fit into the frame at
the same time.
(12) Heat the outer bearing stop in an oven to
a temperature of 150 C. and slide into
Remove the protective paper from the
commutator and turn the armature by
place as shown on the bearing assembly
hand to make certain it is free.
drawing. As it cools, tap with a hammer
to make sure of tight contact against the
Check for proper clearance of one-eighth
inner bearing race.
of an inch between brushholders and
m. Armature Assembly into Frame.
Lower the brushes and fit to the
(1) It is important that the frame be place(d
commutator, using a medium grade of
so that it is in the true vertical position.
Otherwise, the commutator end bearing
cartridge and the pinion end housing may
Blow out carbon dust with dry,
enter their respective fits in a COCKED
Replace the commutator covers.
(2) Wrap a piece of fishpaper or other
protecting material around the
Section X. MISCELLANEOUS CONTROL EQUIPMENT
86. Master Controller
c. When reassembling the drums, first insert the
dowel pin and then tighten the two bolts at the rear
a. The fingers are cam operated double break and
corners of the top plate. This positions the drums with
require no attention other than to see that the contacts
respect to the cam switches. Tighten the two bolts at
are clean and that no springs are broken. The finger
the rear corners of the bottom plate last.
board is easily removed by taking out the two screws at
each end of the finger board. All rollers should be
examined occasionally to see that they turn freely. The
contact pressure is 7 ounce minimum on each contact.
a. Description. The reverser consists of a drum
b. To remove the drums from the backplate and
(with insulated copper segments) capable of rotation
cam switches, remove the dowel pin from the top plate
through a small angle, two air cylinders with pistons for
at rear left center, then remove the two bolts at the rear
drum rotation, control magnet valves, power and control
corners of the top plate and the corresponding two bolts
fingers and an insulating
from the bottom plate. The drums will then be free and
can be removed by moving them forward.