Vacuum Unit Removal And Installation; Rotor - Jeep 1979 CJ-5 Technical & Service Manual

IGNITION SYSTEM 1G-17
(9) If vacuum unit Is to be replaced, remove screws
and lift vacuum unit out of distributor housing. Do not
remove vacuum unit unless replacement is required.
Installation
(1) If vacuum unit was removed, install unit and
attaching screws to distributor housing.
N O T E : If replacement vacuum unit is installed, refer
to Vacuum Unit for calibration procedure.
(2) Position sensor assembly into distributor
housing.
(3) Be sure pin on sensor fits into hole in vacuum
unit link on six-cylinder. Install vacuum unit lever and
retainer to sensor pin on eight-cylinder.
(4) Install washers and retainer onto pivot pin to
secure sensor assembly to base plate on six-cylinder.
Install snap-ring on eight-cylinder.
(5) Position wiring harness in slot in distributor-
housing. Install ground screw through tab and tighten.
(6) Install trigger wheel to shaft with long portion
of teeth upward using hand pressure. When trigger
wheel and slot in shaft are properly aligned, use suitable
drift and small hammer to tap pin into locating groove
in trigger wheel and shaft. If distributor is out of engine,
support shaft while installing trigger wheel pin.
(7) Install rotor. Install distributor cap.
Vacun Unit
Removal
(1) Remove vacuum line from vacuum unit.
(2) Six-cylinder—remove attaching screws and re-
move vacuum unit from distributor body. It is necessary
to tip unit to disengage link from sensor pin protruding
through distributor body. It may be necessary to loosen
base plate screws for necessary clearance.
(3) Eight-cylinder—remove distributor cap. Re-
move retainer from sensor pin. Remove attaching
screws and lift vacuum unit from distributor body.
Installation
(1) If replacement vacuum unit is to be installed,
calibrate as follows:
(a) Insert Allen wrench into vacuum hose tube
of original vacuum unit. Count number of clockwise
turns necessary to bottom adjusting screw.
(b) Turn adjusting screw of replacement vac-
uum unit clockwise to bottom. Turn counterclockwise
same number of turns counted in step (a).
(2) Six-cylinder—install vacuum unit to distributor
body. Be sure that vacuum advance link is engaged on
pin of sensor. Install retaining screws. Tighten base
plate screws, if loosened.
(3) Eight-cylinder—install vacuum unit to distribu-
tor body. Install retaining screws. Position vacuum unit
lever onto sensor pin and install retainer. Install distrib-
utor cap.
(4) Check timing and adjust if required.
(5) Install vacuum line to vacuum unit.
liter
Inspect the rotor during precision tune-ups as out-
lined in Chapter 1A—General Service and Diagnosis. A
new feature of the SSI system is the silicone grease
applied to the rotor blade during manufacture. Radio
interference is greatly reduced by the presence of a
small quantity of silicone grease on the rotor blade.
After a few thousand miles, this grease becomes charred
by the high voltage carried by the rotor (fig. 1G-7). This
is normal. Do not scrape the residue from the rotor
blade.
When installing a replacement rotor, apply a thin coat
(0.03 to 0.12 inch) of Jeep Silicone Dielectric Compound,
or equivalent, to tip of the rotor blade.
7 0 8 7 1
Fig. 1G-7 Rotor Grease Application