Pontiac FIREBIRD 1972 Service Manual page 804

1972 PONTIAC SERVICE MANUAL
NOTE: It will be observed that rotor is doweled
to weight base so that it can be installed in only
one position.
Remove both weight springs and both advance
weights.
Remove R.F.I. shield.
Remove retaining pin from gear by driving it out of
gear with a drift and hammer.
CAUTION: Distn3utor should
be supported in
such a way that distributor shaft will not
be
damaged when driving pin out.
Slide gear and washer off shaft.
Pull shaft and cam-weight base assembly from the
housing.
Remove contact set assembly.
Remove condenser hold-down screw, condenser and
bracket from the breaker plate.
Remove spring retainer and raise plate from housing.
Remove two attaching screws and lock washers and
plate ground lead, and remove vacuum advance unit.
Remove felt washer from around bushing in housing.
ASSEMBLE
Assembly of the distributor is reverse of disassembly
procedure outlined above. When installing gear on shaft,
use a new retaining pin. The pin must be tight in hole to
prevent any movement between gear and shaft.
Note that rotor can be installed in only one position. It
will be broken if an attempt is made to install it back-
wards.
NOTE: All engines with 60 p.s.i oil pump in-
corporate distributors with phosphate coat&
hardened d i v e gears. Whenever one of these
distributors or gears is replaced, an identical
replacement part must be used.
INSTALL
1. Check to see that engine is at firing position for No.
1 cylinder (No. 1 piston at top of compression stroke)
and timing mark on harmonic balancer is indexed
with the proper mark on the timing chain cover (Fig.
6E-54).
position new distributor to block gasket on block.
Install distributor in block so that vacuum dia-
phragm faces left side of engine and rotor points
toward contact in cap for No. 1 cylinder. Before in-
stalling distributor, index rotor with housing as noted
when distributor was removed. This will simplify in-
dexing distributor shaft and gear with oil pump drive
shaft and drive gear on camshaft. Distributor and
rotor will be positioned as shown in Fig. 6E-53 when
properly installed with No. 1 piston in firing position.
Replace distributor hold-down clamp, leaving screw
loose enough to allow distributor to be turned for
timing adjustment.
Attach distributor to coil p'rimary wire.
Replace distributor cap.
Adjust dwell and timing and then tighten distributor
clamp screw.
Attach vacuum hose to distributor.
tor,
1.
2.
3.
If engine was cranked with distributor removed and/or
position of rotor was not noted during removal of distribu-
it may be installed by the following method.
Remove No. 1 spark plug (forward plug of left bank
on V-8).
Place finger in spark plug hole and turn engine over
manually until timing mark is at index (see Fig. 6E-
54).
NOTE: As engine approaches timing mark, a
pressure. should be felt with the finger in the
spark plug hole. If no pressure is felt, it will be
necessary to turn the engine one complete revo-
lution and again index with timing marks.
Install distributor in position as shown in Fig. 6E-53.
It will be necessary to rotate rotor slightly to the right
when attempting installation so that final position
will be correct.
NOTE: If distributor does not drop into posi-
tion fully, hold down on housing and rotate
engine until distributor drops into position.
IGNITION TIMING
'
Timing marks are located on the front engine cover and
harmoqic balancer (Figs. 6E-49, 6E-54 and 6E-55).
It is mandatory to disconnect distributor vacuum advance
hose before setting ignition timing.
At time spark is adjusted, the general appearance of
breaker points should be observed. If smudge line appears