Pontiac tempest 1968 Service Manual page 350

6E-1
ENGINE ELECTRICAL
NOTE: Information pertaining to chassis electrical will be found in Section 12.
CONTENTS OF
SUBJECT PAGE
Cranking Circuit 6E-1
Starting Motor . . . . . . . . . . . . . . . 6E-1
Charging Circuit 6E-7
Generator 6E-7
CSI Generator Regulator 6E-11
Standard and Transistor Regulator . . . . 6E-13
THIS SECTION
SUBJECT PAGE
Ignition Circuit 6E-13
Distributor 6-Cyl. 6E-13
Distributor ¥ - 8 6E-15
Ignition Timing 6E-19
Ignition and Starting Switch . . . . . . . . 6E-19
Spark Plugs 6E-21
CRANKING CIRCUIT
STARTING MOTOR
PERIODIC SERVICE
No periodic lubrication of the starting motor or
solenoid required. The motor and brushes cannot
be inspected without disassembling the unit, so no
service is required on the motor or solenoid between
overhaul periods.
CHECKS AND ADJUSTMENTS ON CAR
Although the starting motor cannot be checked
against specifications on the car, a check can be
made for excessive resistance in the cranking cir­
cuit. To check for excessive resistance in the crank­
ing circuit, measure:
1. The voltage drop, during cranking, between the
positive battery p o s t and battery terminal of
solenoid.
2. The voltage drop, during cranking, between the
battery terminal of solenoid and the motor terminal
of solenoid.
3. The voltage drop, during cranking, between the
negative battery post and the starting motor frame.
CAUTION: To prevent the engine from firing
during the above checks, disconnect the primary
lead to the distributor at the coil.
If the voltage drop for any one of the above three
checks exceeds 0.2 volt, excessive resistance is
indicated in that portion of the cranking circuit being
checked. Locate and eliminate the cause for any
excessive voltage drop in these circuits in order to
obtain maximum efficiency of the cranking system.
When the solenoid fails to pull in, the trouble may
be due to excessive voltage drop in the solenoid con­
trol circuit. To check for this condition, close the
starting switch and measure the voltage drop between
the battery terminal of the solenoid and the switch
terminal of the solenoid. Excessive resistance in the
solenoid control circuit is indicated and should be
corrected if the voltage drop exceeds 3.5 volts.
If the voltage drop does not exceed 3.5 volts and
the solenoid does not pull in, measure the voltage
available at the switch terminal of the solenoid. If
the solenoid does not feel warm, it should pull in
whenever the voltage available at the switch ter­
minal is 7.7 volts or more (when the solenoid feels
warm, it will require a somewhat higher voltage to
pull in).
REMOVE
FROM CAR-6 CYL ENGINE
1. Disconnect battery ground cable at battery ter­
minal post.
2. Disconnect battery positive cable and wiring
harness leads from starting motor solenoid.
3. Remove starting motor.
REMOVE FROM
CAi-V-8
ENGINE
1. Disconnect battery to starting motor cable from
battery post.
2. Raise front of car and place car stand under
front suspension.
3. Pull battery cable and solenoid wire loom down
so they hang free of surrounding parts.