from the end of the shaft in the same
the same angular position on the shaft
manner and the same position that the
and measurements made from the same
cold stand-off was taken. The difference
points. Remove the pinion from the shaft
between the hot and cold stand-offs gives
by lightly driving a wedge between the
the advance of the pinion on the shaft.
pinion face and the oil thrower or motor
This advance must fall within the
and bracket.
application limits.
The application
(3) Heating.
temperature given in paragraph 78 is
(a) Heat the pinions uniformly and for a
estimated only and may have to be
sufficient length of time to soak
adjusted by experience to maintain the
thoroughly. Heat the pinion about
advance within the proper limits. If the
10 C. above the application
advance is not within the proper limits, the
temperature given in the motor
pinion must be pulled and re-applied.
general data, paragraph 78. This
(5) Fastening. If the pinion is equipped with a
allows sufficient time to remove the
nut, apply the lockwasher and nut as soon
pinions front the heating source,
as the hot advance is taken. Screw the
clean the bore and check the
pinion nut home tightly with a wrench
temperature before applying.
having a purchase leverage of 4 to 6 feet.
e. Removal of Armature from Motor. If it is
pinions in the order of preference
necessary to remove the armature from the motor, the
are given below:
following procedure is to be followed:
(1) Take off the pinion nut to provide means
2. Electric oven.
of lifting the armature. Pull the pinion if
3. Gas oven.
the pinion end bearing is to be
4. Oil (only as a last resort).
dismantled. Refer to removal of traction
motor pinions, c above.
(c) If oven facilities are not available,
an electric roaster will work
(2) Remove tile commutator covers and lift
satisfactorily on all pinions up to an
brushes far enough out of brush box so
outside diameter of 12 inches.
that they will not slide back against
Pinions must never be heated
commutator.
above 200C.
(3) Protect the commutator by wrapping it
(d) If oil is used to heat the pinions,
with heavy fishpaper.
they must be thoroughly cleaned
(4) Remove the bolts holding the bearing
with benzol and dry rags to remove
cartridge to the lousing at the commutator
all traces of oil from the pinion bore
end.
before applying to the shaft.
(5) Turn the motor so that the shaft is in a
(4) Application. Remove the pinion from the
true vertical position with the pinion end
heating source and place near the shaft to
up. Support the motor on blocks to avoid
which it is to be applied. Clean the shaft
damaging the commutator end bearing
and pinion bore very thoroughly with clean
cap.
dry rags to remove all traces of oil.
(6) Remove the bolts holding the pinion en(d
Check the pinion temperature with an
housing to the frame.
electric pyrometer placed as close to the
(7) Insert three 3/4-inch bolts in the three
pinion bore as possible. As soon as the
tapped holes equally spaced around the
pinion temperature comes down to the
housing. Tightening up on these bolts
prescribed application temperature the
pulls the housing out of the frame fit.
pinion should be applied on the shaft in
(8) Screw a special lifting nut on the pinion
exactly the same angular position and in
end of the shaft and lift the armature out
the same manner as for the cold standoff.
of the frame with both bearing assemblies
The same mechanic who applied the
intact.
pinion cold should apply the pinion hot in
order to obtain the same force or push.
may be clamped in a wooden saddle in a horizontal
Measure the hot stand-off of the pinion
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