1967 CHEVROLET CAMARO electrical

ENGINE-ELECTRICAL 6Y-28

terminals on eoil. On Corvettes equipped with radio,

remove bolts securing ignition shield over distribu-

tor and coil.

2.
Pull high tension wire from center terminal of coil.

3.
Remove the two coil support mounting bolts or loosen

friction clamp screw and remove coil.

4.
Place new coil in position and install attaching bolts

or tighten clamp screw.

5.
Place high tension lead securely in center terminal

of coil and connect ignition switch and distributor

primary leads to terminals on coil. Replace ignition

shield on Corvettes.

6. Start engine and test coil operation.

IGNITION PULSE AMPLIFIER

DISASSEMBLY

To check the amplifier for defective components, pro-

ceed as follows:

1.
Remove the bottom plate from the amplifier.

2.
To aid in reassembly, note the locations of the lead

connections to the panel board.

3.
Remove the three panel board attaching screws, and

lift the assembly from the housing.

4.
To aid in reassembly, note any identifying markings

on the two transistors and their respective locations

on the panel board and heat sink assembly.

5.
Note the insulators between the transistors.and the

heat sink, and the insulators separating the heat sink

from the panel board.

6. Remove the transistor attaching screws, and sepa-

rate the two transistors and heat sink from the panel

board.

7.
Carefully examine the panel board for evidence of

damage.

MOUNTING

SCREW

RESISTOR R5 jgSfe. / DIODE Dl

TRANSISTOR TR2

(UNDERNEATH)

1H L >©V

[So

To
I
/'%**jt\
\
TRANSISTC>R"""

1 X ^^w^ X \ (UNDERNEATH)

9^ESISTORR^^^H|^^^^^H

^B
RESISTOR
R4
^HPH^^H

WM'
RESISTOR
R3
I^B^^^^I^U

N .6 ®

mm

N%|/MOUNTING

• tr^i^w ^\ vjR SCREW

CAPACITOR
Cl\
pNkj^^A^
\
RESISTOR
Rl

MOUNTING ^55S^^ \ CAPACITOR C3

SCREW I RESISTOR R6 CAPACITOR C2

TRANSISTOR TR3
COMPONENT CHECKS (Figs. \7\ and 18i)

With the two transistors separated from the assembly,

an ohmmeter may be used to check the transistors and

components on the panel board for defects. An ohmmeter

having a 1-1/2 volt cell, which is the type usually found

in service stations, is recommended. The low range

scale on the ohmmeter should be used except where

specified otherwise.

A 25 watt soldering gun is recommended, and a 60% tin

40%
lead solder should be used when re-soldering. Avoid

excessive heat which may damage the panel board. Chip

away any epoxy involved, and apply new epoxy which is

commercially available.

In order to check the panel board assembly, it is

necessary to unsolder at the locations indicated in Fig-

ure 18i the two capacitors C2 and C3. In all of the fol-

lowing checks, connect the ohmmeter as shown and then

reverse the ohmmeter leads to obtain two readings. The

amplifier circuitry is shown in Figure 19i.

1.
Transistors TR1 and TR2: Check each transistor by

referring to Figure 20i. If both readings in Step 1

are zero, the transistor is shorted. If both readings

in Step 2 are zero, the transistor is shorted; and if

both readings are infinite, the transistor is open.

Interpret Step 3 the same as Step 2.

2.
Trigger Transistor TR3:
11
both readings in Step 1

are zero, the transistor is shorted. If both readings

in Step 2 are zero, the transistor is shorted; and if

both readings are infinite, the transistor is open.

Interpret Step 3 the same as Step 2.

3.
Diode Dl: 11 both readings are zero, the diode is

shorted; and if both readings are infinite, the diode

is open.

4.
Capacitor Cl: If both readings are zero, the capaci-

tor is shorted.

5.
Capacitors C2 and C3: Connect the ohmmeter across

CHECKING

RESISTOR Rl

UNSOLDER
I
CHECKING TRIGGER

TRANSISTOR TR3
CHECKING

CAPACITOR C

Fig.
171—Pulse Amplifier Panel Board
Fig.
18i—Pulse
Amplifier
Component
Checks

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-29

each capacitor (not illustrated). The capacitor is

shorted if both readings are zero.

6. Resistor Rl: The resistor is open if both readings

are infinite.

7. Resistor R2: Use an ohmmeter scale on which the

1800 ohm value is within, or nearly within, the

middle third of the scale. If both readings are infi-

nite, the resistor is open.

8. Resistor R3: Use an ohmmeter scale on which the

680 Ohm value is within, or nearly within, the middle

third of the scale. If both readings are infinite, the

resistor is open.

9. Resistor R4: Select an ohmmeter scale on which the

15000 ohm value is within, or nearly .within, the

middle third of the scale. If either reading is infi-

nite, the resistor is open. ~

10.
Resistor R5: Use the lowest range ohmmeter scale.

The resistor is open if either reading is infinite.

NOTE:
This resistor on some applications may

be located in the vehicle wiring harness, and not

on the panel board.

11.
Resistor R6: An ohmmeter scale on which the 150

ohm value is within or nearly within, the middle

third of the scale should be used. If both readings

are infinite, the resistor is open.

REASSEMBLY

During assembly, coat with silicone grease both sides

of the flat insulators used between the transistors and

heat sink, and also the heat sink on the side on which the

transistors are mounted. The silicone grease, which is

available commercially, conducts heat and thereby pro-

vides better cooling.'

IGNITION PULSE AMPLIFIER

R-5

C-3 Ju

MAGNETIC PULSE

DISTRIBUTOR
IGNITION SWITCH REPLACEMENT (Figs.
21
i to 23i)

CHEVROLET, CHEVY II AND CORVETTE

1.
Raise hood and disconnect battery ground cable from

battery.

2.
Remove lock cylinder by positioning switch in "off"

position and inserting wire in small hole in cylinder

face. Push in on wire to depress plunger and con-

tinue to turn key counter-clockwise until lock cylin-

der can be removed.

3.
Remove the metal ignition switch nut from the pas-

senger side of the dash using Tool J-7607 (Fig. 21i).

4.
Pull the ignition switch out from under the dash and

remove the wiring connectors.

5. To remove the "theft resistant" connector, the

switch must be out from under the dash as outlined

in Step 4. Using a screw driver unsnap the locking

tangs on the connector from their position on the

switch as shown in Figure 22i. Unplug the connector.

6. Snap the connector into place on a new ignition

switch.

7. Place the switch into position from behind the dash

and install the metal ignition switch nut.

8. Install the lock cylinder.

9. Install the battery cable to the battery and lower the

hood.

CHEVELLE

1.
Disconnect battery ground cable.

2.
Remove ash tray, retainer attaching screws and

retainer.

3.
Remove A/C distributor duct retaining screws and

duct.

Fig.
19i—Pulse Amplifier Internal Circuitry
Fig.
20i—Transistor Checking

CHEVROLET Oi

ENGINE-ELECTRICAL-6Y-30

Fig.
2 li—Removing Ignition Switch Nut

4.
Remove heater and/or A/C control panel assembly

retaining screws and push panel assembly from

console.

NOTE: If interference between control panel

and radio is encountered, loosen radio retaining

nuts.

5.
Remove radio control knobs, bezels and retaining

nuts.

6. Disconnect radio wiring harness and antenna lead-in.

7.
Remove radio rear brace attaching screw and re-

move radio from vehicle.
Fig.
231—Switch and Connector Unplugged

8. Remove ignition switch bezel nut using Tool J-7607

and push switch rearward from panel opening.

9. Disconnect wiring connector from rear of switch.

10.
To install, reverse removal procedure.

SPARK PLUGS

CLEANING AND REGAPPING

Clean the spark plugs thoroughly, using an abrasive-

type cleaner. If the porcelains are badly glazed or

blistered, the spark plugs should be replaced. All spark

plugs must be of the same make and number or heat

range. Use a round feeler gauge to adjust the spark plug

gap to specifications (fig. 24i).

Fig.
22i—Unlocking Ignition Switch Connector

Fig.
241—Setting Sfxirk Plug Gap

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL
6Y-31

CAUTION: Before adjusting gap, me center
INSTALLATION

electrode flat. In adjusting the spark pluig Install the spark plugs in the engine with new gaskets

gap,
never bend the center electrode which and tighten to specifications. If torque wrench is not

extends through the porcelain center. Always available, tighten plugs finger tight and 1/2 turn more.

make adjustment by bending the ground or , Plugs are of a 14 millimeter size and care must be

side electrode. exercised when installing or the gap setting may be

changed.

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-32

STARTER CIRCUIT

INDEX

Page

General Description 6Y-32

Maintenance and Adjustments . '. . 6Y-32

Resistance Checks 6Y-32

Starting Motor and Solenoid Check 6Y-33
Page

Service Operations 6Y-33

Starter Motor 6Y-33

Removal and Installation 6Y-33

GENERAL DESCRIPTION

The function of the starting system, composed of the

starting motor, solenoid and battery, is to crank the

engine. The battery supplies the electrical energy, the

solenoid completes the circuit to the starting motor, and

the motor then does the actual work of cranking the

engine.

The starting motor (fig. Is) consists primarily of the

drive mechanism, frame, armature, brushes, and field

windings. The starting motor is a pad mounted 12-volt

extruded frame type, having four pole shoes and four
fields,
connected with the armature. The aluminum drive

end housing is extended to enclose the entire shift lever

and plunger mechanism, protecting them from dirt,

splash, and icing. The flange mounted solenoid switch

operates the overrunning clutch drive by means of a

linkage to the shaft lever.

The V-8 wiring harness differs from the in-line engine

in that the ignition lead to the coil from the switch is at-

tached at the coil instead of at the starter solenoid (fig.

2s).

CONTACT

FINGER

PINION

STOP

BRUSH

INSULATED BRUSH HOLDER \ FIELD COIL

BRUSH SPRING ARMATURE

GROUNDED BRUSH HOLDER
OVERRUNNING

CLUTCH

Fig.
Is—Starting Motor Cross Section (Typical)

MAINTENANCE AND ADJUSTMENTS

No periodic lubrication of the starting motor or sole-

noid is required. Since the starting motor and brushes

cannot be inspected without disassembling the unit, no.

service is required on these units between overhaul

periods.

RESISTANCE CHECKS

Although the starting motor cannot be checked against
specifications on the car, a check can be made for. exces-

sive resistance in the starting circuit. Place a volt-

meter across points in the cranking circuit as outlined

below and observe the reading with the starting switch

closed and the motor cranking (distributor primary lead

grounded to prevent engine firing).

1.
From battery positive post To solenoid battery

terminal.

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-33

O

V-8 ENGINE
STARTING MOTOR

Fig.
2s—V-8 Starting Circuit Diagram

2.

3.
From battery negative post
To
starting motor

housing.

From solenoid battery terminal
To
solenoid motor

terminal.

If voltage drop
in
any
of
above check exceeds 0.2 volts,

excessive resistance
is
indicated in that portion
of
start-

ing circuit
and the
cause
of the
excessive resistance

should
be
located
and
corrected
in
order to obtain maxi-

mum efficiency in the circuit.

CAUTION:
Do not
operate
the
starting motor

continuously
for
more than
30
seconds
to
avoid

overheating.

When
the
solenoid fails
to
pull
in, the
trouble may be

due
to
excessive voltage drop in the solenoid control cir-

cuit.
To
check
for
this condition, close
the
starting

switch
and
measure
the
voltage drop between
the
BAT-

TERY terminal of the solenoid and the
SWITCH (S)
termi-

nal
of
the solenoid.
1.
If
this voltage drop exceeds 3.5 volts, excessive
re-

sistance
in the
solenoid control circuit
is
indicated

and should be corrected.

2.
If the
voltage drop does not exceed 3.5 volts and the

solenoid does not pull in, measure the voltage availa-

ble
at
the SWITCH terminal
of
the solenoid.

3.
If the
solenoid does
not
feel warm,
it
should pull
in

whenever the voltage available
at
the SWITCH termi-

nal
is 7.7
volts
or
more. When
the
solenoid feels

warm,
it
will require
a
somewhat higher voltage
to

pull in.

STARTING MOTOR AND SOLENOID CHECK

The following checks
may be
made
if the
specific

gravity of the battery
is
1.215
or
higher.

1.
If the
solenoid does
not
pull in, measure the voltage

between
the
switch
(S)
terminal
of the
solenoid
and

ground with the starting switch closed.

CAUTION:
If the
solenoid feels warm, allow
to

cool before checking.

If
the
voltage
is
less than 7.7 volts, check for ex-

cessive resistance
in the
solenoid control circuit.

If
the
voltage exceeds 7.7 volts, remove the starting

motor
and
check
(1)
solenoid current draw,
(2)

starting motor pinion clearance,
and (3)
freedom of

shift lever linkage.

2.
If
the solenoid "chatters" but does not hold in, check

the solenoid
for an
open "hold-in" 'winding. When-

ever
it is
necessary
to
replace
a
starting motor

solenoid, always check starting motor pinion

clearance.

3.
If
motor engages
but
does
not
crank
or
cranks

slowly, check
for
excessive resistance
in the ex-

ternal starting circuit, trouble within
the
starting

motor,
or
excessive engine resistance
to
cranking.

SERVICE OPERATIONS

STARTING MOTOR

REMOVAL AND INSTALLATION (Fig.
3s)

The following procedure
is a
general guide
for all

vehicles
and
will vary slightly depending
on
series
and

model.

1.
Disconnect battery ground cable at battery.

2.
Raise vehicle
to a
good working height.

3.
Disconnect all wires
at
solenoid terminals.

NOTE: Reinstall
the
nuts
as
each wire
is
dis-

connected
as
thread size
is
different but may be

mixed and stripped.

4.
Loosen starter front bracket (nut on V-8 and bolt on

L-6) then remove two mount bolts.

5.
Remove
the
front bracket bolt
or nut and
rotate

bracket clear
of
work area then lower starter from

vehicle
by
lowering front end first
—
(hold starter

against bell housing
and
sort
of
roll end-over-end).

6. Reverse
the
removal procedure
to
install. Torque

the mount bolts
to
25-35
ft.
lbs. first, then torque

brace bolt.

7.
Check operation
of
starter on vehicle.
Fig.
3s—Starter Mounting

CHEVROLET CHASSIS SERVICE MANUAL

ENGINE-ELECTRICAL 6Y-34

SPECIAL TOOLS

J-7607

IGNITION SWITCH

NUT REMOVER

J-9717-2

SUPPORT

TOOL
J-9717-1

PRESS

TOOL
J-9600-2

SHOULDERED

INSTALLER
J-21501

PULLY

ADAPTER

J-5184

CHECKING

SCALE

J-21600

HARNESS ADAPTER

Fig. 4s-Specia! Tools

CHEVROLET CHASSIS SERVICE MANUAL

CLUTCH AND TRANSMISSIONS 7-9

6. Connect speedometer cable.

7. Install propeller shaft assembly.

8. Fill transmission with lubricant specified in Section

O.

CORVETTE TRANSMISSION REPLACEMENT

, 1. Disconnect battery ground cable.

2.
Pisassemble transmission shift control lever by un-

screwing ball from lever, lifting out
"T"
handle re-

turn spring and "T" handle, then remove the anti-

rattle bushings.

3.
Raise front and rear of vehicle.

4.
Insert a block of wood between the top of the dif-

ferential carrier housing and the underbody (to pre-

vent upward travel of the carrier when the carrier

front support is disconnected).

5. Disconnect the differential carrier front supportfrom

its frame bracket, by removing the nut on the under-

side of the biscuit mount.

6. Pry the carrier downward to relieve load while re-

moving the two center mounting bolts from the car-

rier front support. (To pry carrier downward insert

crowfoot end of a pry bar through the opening in the

carrier front support, hooking end of bar over top of

the center mounting bolt pad cast in the underside of

the carrier.)

7. Pivot carrier support downward for access to prop

shaft "U" joint.

8.
.
Disconnect prop shaft front and then rear "U" bolts.

9. Disconnect parking brake cable from ball socket at

idler lever located near center of underbody.

10.
Remove prop shaft by moving shaft forward.

11.
Remove heat deflectors from the right and left ex-

haust pipe.

12.
Remove left bank exhaust pipe.

13.
Remove right bank exhaust pipe and heat riser.

14.
Disassemble the transmission mount, as follows:

a. Remove the two bolts that attach rear mount

cushion to the rear mount bracket.

b.
Support engine under oil pan and raise engine to

remove load from rear mount cushion.
CAUTION: To avoid damage to oil pan, a suit-

able wide base, heavy wood platform should be

placed between the jack pad and the oil pan.

c. Remove the three transmission mount bracket-

to-
crossm ember bolts and remove mount bracket.

d. Remove the two bolts from mount pad to trans-

mission case and remove rubber mount cushion

and exhaust pipe "yoke".

15.
Disconnect transmission linkage by removing the

shift levers at the transmission side cover.

16.
Disconnect speedo cable at transmission extension.

17.
Remove transmission output shaft slip yoke.

NOTE:
The yoke is removed to avoid tearing

the heat reflecting pad on the underbody, when

the transmission is being removed.

18.
Remove two bolts to disconnect the transmission

gearshift control lever and bracket assembly from

its adapter plate on side of transmission. Lower

transmission assembly from the vehicle, letting the

gearshift lever slide down and through the dust boot

in the console.

19.
Remove transmission-to-clutch housing attaching

bolts.

20.
Slide transmission assembly rearward from clutch

and rotate transmission for access to the three flat

head machine screws in the control lever bracket

adapter plate. Remove adapter plate. Rotate trans-

mission back to the upright position.

21.
To allow room for transmission removal slowly

lower the rear of engine until the tachometer drive

cable at the distributor just clears the horizontal

ledge across the front of dash.

CAUTION: The tachometer cable can be easily

damaged by heavy contact with the dash. Slide

transmission rearward out of the clutch, then

tip front end of transmission downward and

lower the assembly from vehicle.

22.
Reinstall transmission assembly by performing above

steps in reverse order.

TRANSMISSION OVERDRIVE

INDEX

Page

General
Description 7-10

Maintenance
and Adjustments 7—10

Governor
Switch and Pinion .............. 7-10

Sun
Gear Solenoid Oil Seal and Control

Cable
Bracket 7-10

Case
Rear Oil Seal 7-10

Removal
7-10

Installation
. . . . . 7-10

Control
Shaft Lever and Oil Seal 7-10

Speedometer
Driven Gear 7-10

Electrical
Unit Checks 7-11

Overdrive
Relay . 7-11
Page

Air
Gap 7-11

Point
Opening 7-11

Closing
Voltage 7-11

Solenoid
. 7-11

Closing
Coil 7-11

Engaging
Spring . - 7-11

Ignition
Grounding Contact . 7-11

Governor
Switch 7-11

Kickdown
Switch 7-11

Diagnosis
- Overdrive 7-12

Mechanical
. 7-12

Electrical
7-13

CHEVROLET CHASSIS SERVICE MANUAL