1917 Cadillac - GM Heritage Center

ADJUSTMENTS 89
TO ADJUST AXLE PINION AND DRIVING GEAR
In the design of the axle, provision is made for adjusting the pinion and
gear so that the teeth may be correctly meshed, and for locking all the
adjusting nuts securely in position.
The large bevel gear "A," Fig. 50, on the gear mount "B" and the bevel
pinion "C" on the driving shaft "D" are correctly meshed when the car is
assembled, but after it has been in use for several thousand miles, it may be
found that the bearings "E" and "F" which take the end thrust of the gears
have become more permanently seated, causing end play in the pinion shaft
"D" and side play in the gear mount "B." When this condition exists, bearings
"E" and "F" should be readjusted.
If undue end play exists in the pinion shaft "D," the bearing "E" should
be adjusted as follows:
Remove the two clamp bolts "G," then remove the key "Y" and the cap
"H." Hold the adjusting nut "I" from turning and turn up the adjusting
nut "K" as far as possible without making the bearing "E" too tight. (See
under "Caution in Adjusting Timken Bearings," page 84.) After the adjustment
has been made replace the key "Y," the cap "H" and the clamp bolts "G."
If, after removing the rear cover plate "L," undue side play is found in
the gear mount "B," the bearing "F" should be adjusted as follows:
Move the key "M" entirely out of the slots in the adjusting nut "N,"
loosen the cap screws holding the cap "O" and turn the adjusting nut "N"
as far as possible without making the bearings too tight. (See under "Caution
in Adjusting Timken Bearings," page 84.) After the adjustment has been
made, make sure that the key "M" is replaced in one of the slots in adjusting
nut "N" and that the cap screws holding the cap "O" are tightened and
locked.
If after adjusting the. bearings "E" and "F" it is found necessary to
move the pinion "C" endwise or the bevel gear "A" sidewise in order to
bring the gears into proper mesh, it must first be determined whether it is
necessary to move the pinion, the large bevel gear, or both, and in which
direction the gear or gears must be moved.
Bevel gears should be so adjusted that the large ends of the teeth of
one gear are practically flush with the large ends of the teeth of the other
gear, which can be determined by removing the peep hole cover "V." Extreme
care must be used in adjusting, as the tooth forms of the most accurately cut
gears may be easily ruined by running them when not properly meshed.
In order to adjust, the gears to the best advantage, a crank should be
attached to the forward end of the pinion shaft "D" so that the gears can
be turned by hand and the adjustment tried until positions are found for the
gears where they run smoothly and do not bind at any point.
If the bearings "E" and "P" on the drive shaft "D" are in proper adjustment
and if it is found necessary to move the pinion "C" endwise, proceed
as follows:
Remove the clamp bolts "G," the key "Y" and the cap "H." Move the
adjusting nuts "I" and "K'' together, moving the pinion in either direction as
required. If the adjusting nuts "I" and "K" are moved in the same direction
and exactly together the relative adjustment of the bearings "P" and "E" will
not be altered.
When the proper position for the pinion has been found, replace the cap
"H," the key "Y" and the clamp bolts "G."