Chevrolet 10 Series 1968, Service Manual

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E N G IN E -E LE C TR IC A L 6 Y -2 2
F ig . 5 i—C h e ckin g Breaker Arm Spring Tension
CA U TIO N :
Carefully wipe protective film from
point set prior to installation.
PRIMARY
LEAD
NOTE: Pilot on contact set must engage match­
ing hole in breaker plate.
7. Connect primary and condenser lead wires to quick
disconnect terminal on contact point set.
8
. Check and adjust points for proper alignment and
breaker arm spring tension (fig. 5i). Use an aligning
tool to bend stationary contact support if points need
alignment.
NOTE: The contact point pressure must fall
within specified limits. Weak tension will cause
chatter resulting in arcing and burning of the
points and an ignition miss at high speed, while
excessive tension will cause undue wear of the
contact points, cam and rubbing block. Breaker
arm spring tension should be 19-23 ounces. The
contact point pressure should be checked with a
spring gauge. The scale should be hooked to the
breaker lever and the pull exerted at 90 degrees
to the breaker lever as shown in Figure 5i. The
reading should be taken just as the points sepa­
rate. The pressure can be adjusted by bending
the breaker lever spring. If the pressure is ex­
cessive, it can be decreased by pinching the
spring carefully.
To increase pressure, the
lever must be removed from the distributor so
the spring can be bent away from the lever.
Avoid excessive spring distortion.
9. Set point opening (.019" for new points).
10. Reinstall rotor, position and lock distributor cap to
housing.
11. Start engine and test dwell and ignition timing.
Eight Cylinder Engine Distributor
1. The contact point set is replaced as one complete
assembly and only dwell angle requires adjustment
after replacement. Breaker lever spring tension and
point alignment are factory set.
2. Remove the distributor cap by placing a screw driver
in the slot head of the latch, press down and turn 1/4
turn in either direction.
3. Remove the two attaching screws which hold the base
of the contact set assembly in place.
4. Remove the primary and condenser leads from their
nylon insulated connection (fig.
6
i) in contact set.
F ig . 6 i—Distributor Lead Arrangements
5. Reverse Steps 2, 3 and 4 to install new contact set.
CA U TIO N :
Install the primary and condenser
leads as shown in Figure 6 i. Improper installa­
tion will cause lead interference between the
cap, weight base and breaker advance plate.
6
. If car has 20,000 to 25,000 miles (or sooner if
desired) the cam lubricator wick (fig. 7i) should be
changed. Using long nosed pliers squeeze assembly
together at base and lift out. Remove all old lubri­
cant from cam surface. Replace in same manner.
F ig . 7 i—Top View of Distributor
ROTOR
CAM
LUBRICATOR
REPLACEMENT
CAUTION!
NEVER OIL
CAM LUBRICATOR—
REPLACE WICK
WHEN NECESSARY
ADJUST SQUARELY
AND JUST
TOUCHING LOBE
OF CAM
LOCATOR
(RO U N D )
CENTRIFUGAL
ADVANCE
MECHANISM
LOCATOR
(SQ U ARE)
CAM
LUBRICATOR
CHEVROLET TRUCK SERVICE MANUAL