Adjusting Dwell Angle - Pontiac Grand Prix Service Manual

6E-16
1969
PONTIAC SERVICE MANUAL
Fig. 6E-28 Adjusting Dwell Angle
1 cylinder (No. 1 piston at top of compression stroke)
and timing mark on harmonic balancer is indexed
with the proper mark on the lower timing belt cover
(Fig. 6E-33).
2. Position new distributor to block gasket on block.
3. Before installing distributor, index rotor with
housing as noted when distributor was removed, Fig.
6E-32. This will simplify indexing the distributor shaft
and gear with oil pump drive shaft and distributor
drive gear. Distributor and rotor will be positioned
properly when installed with No. 1 piston in firing
position.
4. Replace distributor clamp leaving nut loose enough
to allow distributor to be turned for timing adjustment.
5. Attach distributor to coil primary wire.
6. Replace distributor cap.
7. Adjust timing and then tighten distributor clamp
nut.
8. Attach vacuum line to distributor.
DISTRIBUTOR
-
8 CYLINDER ENGINE
PERIODIC SERVICE
A permanent lubricant reservoir is built into the
distributor housing to lubricate upper end of shaft. No
periodic lubrication is required.
When replacing contact set assembly, apply a trace of
petrolatum to breaker cam. No other lubrication is
required. The movable breaker plate is lubricated by
lubricant from the upper shaft bushing.
This distributor also requires periodic inspection of cap
and rotor, wiring, and point condition, and a check for
correct spark timing. This should be done at each tune
up and at least every spring and fall.
ADJUSTMENT
1. With engine operating, raise window provided in
cap.
2. Insert Hex type wrench into head of adjusting screw
as shown in Fig. 6E-28.
3. Turn screw to adjust point opening by one of the
following methods:
Preferred Method:
Turn adjusting screw until 30" dwell is obtained as
measured by dwell meter. (When using dwell meter,
be sure to test distributor resistance before testing
dwell angle.)
NOTE: Providing dwell meter is accurate and is used
correctly, points can be set very ahurately. Several
&sign features such ar ure of upper shaft bushing as a
bearing for breaker plate and construction of advance
mechanism have made this possible.
Alternate Method:
Turn adjusting screw (clockwise) until engine begins to
misfire. Then turn screw one-half turn in opposite
direction (counterclockwise). This will give proper
dwell angle.
REMOVE
1. Disconnect distributor-to-coil primary wire.
2. Remove distributor cap.
3. Crank engine so rotor is in position to fire No. 1
cylinder and timing mark on harmonic balancer is
indexed with the proper mark on the timing chain
cover, Fig. 6E-3 1 and 6E-34.
4. Remove vacuum line from distributor
5. Remove distributor clamping screw and hold-down
clamp.
6. Remove distributor and distributor to block gasket.
It will be noted that rotor will rotate as distributor is
pulled out of block. Note relationship of rotor and
distributor housing after removal, so that rotor can be
set in same position when distributor is being installed.
NOTE: Always set distributor in upright position so oil