Pontiac FIREBIRD 1972 Service Manual page 885

7D- 16 1972 PONTIAC SERVICE MANUAL
Roughness may be determined by slowly turning the
outer race by hand.
All main drive gear and countershaft gear bearing
rollers should be inspected closely and replaced if
they show wear.
Inspect countershaft at the same time and replace if
necessary. Replace all worn bearing washers.
Inspect all gears and 1st speed gear sleeve and, if
necessary, replace all that are worn or damaged.
The bushings used in the rear reverse idler gear are
pressed into the gear, then peened into holes in the
bores and are bored in place. This insures the positive
alignment of the bushings and their shaft, as well as
proper meshing of the gears. Because of the high
degree of accuracy to which these parts are ma-
chined, the bushings are not serviced separately.
Check bushings for excessive wear by using a narrow
feeler gauge between the shaft and bushing or use a
micrometer. The proper clearance is from .003" to
.005".
ASSEMBLE
1. From the rear of mainshaft, assemble the 2nd speed
gear (with hub of gear toward rear of shaft).
2. Install 1st & 2nd speed synchronizer assembly to
mainshaft (synchronizer sleeve taper toward the rear
of the transmission), together with a synchronizer
blocker ring on either side so their keyways line up
with the shifting plates (Fig. 7D-28).
3. Press 1st speed gear sleeve onto mainshaft, using a
1-3/4" I.D. pipe cut to convenient length.
4. Install the 1st speed gear (with hub toward front)
and, using a 1-5/8" I.D. pipe cut to a suitable length,
press on the rear bearing (snap ring groove toward
front of transmission). Firmly seat the bearing (Fig.
7D-29).
Choose the correct selective fit rear bearing retainer
snap ring (.087", .090", .093" or .096) and install it
in the groove in mainshaft behind rear bearing. With
proper ring, maximum distance between snap ring
and rear face of bearing will be from zero to .005".
NOTE:
Always use new rings when reassem-
bling transmission and do not expand the rings
further than is necessary for assembly.
Install the 3rd speed gear (hub t o front of transmis-
sion) and the 3rd speed gear synchronizer blocker
ring (notches to front of transmission).
Install the 3rd & 4th speed synchronizer assembly
with synchronizer sleeve taper toward front, making
sure shifting plates in hub correspond to notches in
the 3rd speed gear synchronizer blocker ring.
Install retainer ring in groove in mainshaft in front of
the 3rd & 4th speed synchronizer assembly, with ends
of ring seated behind spline teeth.
SNAP RING
GROOVE
P I P E
Fig. 7D-28 Installing 1st Speed Synchronizer Blocker Ring
Fig. 7D-29 Installing Rear Bearing