d. Applying Traction Motor Pinions. The following
(5) Remove the straps which hold the motor
nose in place on the truck transom; or
instructions cover the method to be used in applying
block up the motor near the link
pinions to traction motor shafts having a tapered fit.
suspension rod and knock out the pin.
(1) Preliminary precautions.
(6) Lift the motor out of the truck with a
(a) Check the seat on the shaft and the
crane, hooking the lifting chains into the
pinion bore.
Remove all burrs,
bail cast on the motor frame for that
enlargements and galled spots.
purpose. When hooking up the crane
(b) Check the pinion fit on the shaft
chains, if three chains are employed, care
with Prussian Blue. Scrape or stone
should be taken to so adjust the lengths
the pinion bore until at least 75
that the motor will be lifted first on the
percent of the area is in contact.
side next to the truck center, and rotated
The best way to check the fit is to
around the axle a sufficient amount so
blue the shaft, place the pillion on
that the lower lip of the axle bearing
the shaft about 1 inch from its final
housing will clear the axle before the
position and then give a quick
chain attached to the axle side of the
shove home. The pinion can be
motor takes up its slack.
removed by lightly driving a metal
c. Removal of Traction Motor Pinions.
wedge between the pinion face and
(1) Pinions are most easily removed by
the oil thrower or the motor housing.
means of a pinion puller made especially
This should only be done with
to fit the pinion.
pinions applied cold to the shaft.
(2) If desired, a simple "one man" puller that
(c) For pinions with a keyway the key
will meet all requirements can be made
should be a tight fit in the keyway of
the shaft. The keyway in the pinion
The puller should be applied as shown on
may be 0.002 inch larger but not
the tool drawing. In a fully equipped
smaller than the key.
The
service shop, a "power puller" may be
clearance between the top of the
available and can be used, if adaptable.
key and the bottom of the keyway in
the pinion must be at least 1/64
(3) Care should be exercised when removing
inch. Round off the corners of the
motor pinions.
Take the following
key to prevent cutting into the fillet
precautions:
of the keyway. Round the corners
(a) Do not try to remove a "set" pinion
on the lead of the key and the lead
by driving wedges between the
of the pinion keyway to prevent
pinion and the motor housing or oil
galling. Try the cold pinion on the
thrower. Considerable damage will
shaft to make sure that the key will
result to the motor.
not bind and prevent the pinion from
(b) In order to prevent damage to
moving to its proper position.
(2) Cold stand-off. Clean the shaft and the
with a sledge hammer on the pinion
pinion bore thoroughly with benzol or
or pinion puller.
solvent to remove all traces of oil and
(c) Never apply a flame to any pinion
Prussian Blue. With the pinion and the
that is to be put back in service as
shaft at the same temperature, place the
there is great danger of destroying
pinion on the shaft about 1 inch from its
the original heat treatment.
final position and then give a quick shove
(4) In removing a worn pinion that is to be
home. Measure the distance the pinion
scrapped and is very hard to pull, it may
stands off from the end of the shaft with
be necessary to apply heat with a torch to
expand the pinion and relieve the fit.
of measurement and mark across the end
When an old pinion is heated, great care
of the shaft so that after heating the
must be taken to protect the shaft and
pinion, it can be mounted in exactly
housing to prevent their being damaged
by the heat.
41