turn signal CHEVROLET CAMARO 1967 1.G Chassis Owner's Manual

STEERING
9-26

Fig.
54—Corvette Telescoping Column—Exploded View

1.
Wiring Protector

2.
Screw

3. Screw

4. Turn Signal Switch

5. Upper Bearing

Housing

6. Signal Switch Cover

7. Escutcheon
8

9

10

11

12

13

14
8.
Mast Jacket

9. Bumper

Key

Bumper

Bumper Key Strap

Steering Wheel Nut

Upper Bearing Preload

Spring
15.
Cancelling Cam

16.
Retaining Ring

17.
Thrust Washer

18.
Wave Washer

19.
Retainer

20.
Bearing

21.
Spring

22.
Washer
23. Retaining Ring

24.
Lower Steering

Shaft

25.
Upper Steering

Shaft

26.
Locking
Rod

27.
Wedge

Disassembly—Corvette Telescoping Column (Fig. 54).

1.
Place column on a suitable work bench.,

2.
Remove upper bearing preload spring and cancelling

cam from end of shaft.

3.
Remove turn signal lever retaining screw and re-

move lever. Push hazard warning knob in; unscrew

and remove knob.

4.
Remove upper retaining ring from upper steering

shaft using a screwdriver. Remove thrust washer

and wave washer. -

5. Remove three- screws from the lower bearing

retainer.
6. Carefully slide steering shaft assembly out of lower

end of mast jacket.

7. Remove flange bolt and flange from lower end of

shaft. -

CAUTION: Use caution when removing the low-

er retaining ring in the following step. The lower

bearing washer is under load from the com-

pressed spring and could cause injury when the

lower retaining ring is removed.

8. Carefully remove lower retaining ring as shown in

Figure 55. Remove washer* spring, packing, and

CHEVROLET CHASSIS SERVICE MANUAL

STEERING 9-27

Fig.
55— Removing Lower Bearing Retaining Ring

bearing assembly from lower end of shaft.

9. Push upper steering shaft section into lower section

until spring pin is visible at pin access hole in lower

section. Drive out spring pin.

10.
Remove upper shaft section from lower section. If

necessary, replace locking wedge and locking rod at

this time.

11.
Remove bumper key strap (fig. 56). Remove keys and

bumper assembly.

12.
Remove screws securing bottom of wiring protector

to column.

13.
Slide inner jacket section, switch cover, switch,

upper bearing housing, wiring protector, and es-

cutcheon off top end of jacket.

14.
If necessary, remove three turn signal switch mount-

ing screws and remove switch and upper bearing

housing.

15.
If necessary, remove seals from I.D. of mast jacket.

16.
If necessary, unwrap mesh cover from jacket.

Assembly—Corvette Telescoping Column (Fig. 54)

1.
Apply a thin coating of lithium soap grease to all

friction surfaces.

2.
If seals were removed from I.D. of mast jacket,

cement new seals in positions where old seals were

removed.

3.
Place locking wedge and locking rod into upper shaft

and slide upper shaft into lower shaft.

4.
Align upper and lower shafts and insert spring pin

into access hole.

5. Install bearing, packing, spring, washer, and retain-

ing ring on bottom of steering shaft. Seat the re-

taining ring into the steering shaft groove with a

screwdriver.

6. Carefully slide steering shaft into lower end of mast

jacket.

7. Install bearing retainer over lower end of shaft and

lower end of jacket. Secure retainer with three

screws.

8. Install flange and flange bolt on lower end of steering

shaft.

9. Feed wires of turn signal switch through turn signal

switch cover and escutcheon, and place switch and

upper bearing housing in cover. Secure switch to

cover with three mounting screws.
10.
Place wiring protector inside escutcheon.

11.
Start escutcheon and wiring protector, with signal

switch wires, over end of outer jacket.

12.
Slide inner jacket section into outer jacket section.

13.
Secure switch cover to flange of inner jacket section

by tightening the signal switch mounting screws.

14.
Secure the bottom of the wiring protector to the col-

umn with two screws.

15.
Assemble keys and bumper and place the entire as-

sembly in position in the jacket. Install bumper key

strap.

16.
Slide wave washer, thrust washer, and upper retain-

ing ring into place at top of shaft. Seat retaining ring

in steering shaft groove with a screwdriver.

17.
Place turn signal switch lever in position and secure

with screw. Screw hazard warning knob into position.

18.
If mesh cover was removed, wrap mesh cover around

mesh section of jacket and secure with electricians

or friction tape.

19.
Slide cancelling cam and upper bearing preload

spring over top end of shaft.

Installation

NOTE:
Before placing column in position in

vehicle, refer to figures 19 through 23 and slide

dash panel seals, covers, plates, and clamps

loosely into position on column for later

installation.

1.
Move front seat back as far as possible to provide

Fig.
56—Removing Bumper Key Strap

CHEVROLET CHASSIS SERVICE MANUAL

ELECTRICAL-BODY
AND
CHASSIS
12-36

CAMARO INSTRUMENTS AND GAUGES

INDEX

Page

General Description
12-36

Service Operations
12-36

Instrument Cluster
. . . 12-36

Instrument Lamps
12-36

Printed Circuit
12-36

Fuel Gauge
12-37

Tachometer
. . 12-37

Seat Separator Instrument Console
12-37
Page

Fuel Gauge
12-37

Ammeter
12-37

Temperature Gauge
12-37

Oil Pressure Gauge
. 12-37

Fuel Warning Unit
12-37

Clock.
... 12-37

Oil Pressure Indicator
12-37

Generator Indicator
12-38

Temperature Indicator
12-38

GENERAL DESCRIPTION

The standard Camaro instrument cluster assembly con-

sists
of two
circular units which house
the
speedometer

and fuel gauge assemblies.
The oil
pressure, left-hand

directional
and
brake warning indicators
are
located
in

the face
of the
speedometer bezel while generator,
tem-

perature
and
right-hand directional indicators are grouped

with
the
fuel gauge unit.
The
high beam indicator
is

located between
the
cluster bezels.

A special instrumentation package
is
available with
the

eight-cylinder engine
and
center floor console combina-

tion.
The
special cluster includes:
a
clock; coolant

temperature,
oil
pressure, fuel
and
ammeter gauges,

mounted forward
on the
seat separator console;
a ta-

chometer
in the
right circular housing
of the
dash
in-

strument cluster; and
a low
fuel level indicator replacing

the
oil
pressure indicator lamp
in the
instrument cluster.

The instruments
and
gauges,
may be
serviced only

after
the
instrument cluster
is
removed from
the
vehicle.

Indicator
and
cluster lamps except
for the
high beam

indicator
may be
replaced without removing
the
cluster

assembly. Partial cluster removal
is
necessary when

replacing
the
high beam indicator due
to its
proximity
to
the upper brace
rod
anchor plate.
The
bulbs
are in-

stalled
in
plastic sockets which lock into
the
cluster

housing and make contact with
the
printed circuit.

A
low
level fuel warning system
is a
special feature

available with
the
floor console gauge pack. This
sys-

tem includes
an
indicator lamp
in the
dash cluster and
a

semi-conductor unit senses
the
change
in
electrical
re-

sistance
of the
fuel system circuitry
as
variations
in

fuel level occur.
The
sensing device
is
replaced
as a

unit
if
found defective.

The brake warning light serves
a
dual purpose.
It

functions
as an
indicator when
the
parking brake
is ap-

plied
and
also
if
there
is a
malfunction (loss
of
hydraulic

pressure)
in the
brake system. Switches which provide

the signal
to
operate
the
light
are
located
at the
parking

brake assembly
and at the
brake master cylinder
in the

hydraulic lines. Service
of the
brake pressure differ-

ential switch unit
is
covered
in
Section
5 of
this manual.

Regular maintenance
is not
required on
the
instrument

cluster
or its
components other than maintaining clean,

tight electrical connections, replacing defective parts

and keeping
the
speedometer properly lubricated.

SERVICE OPERATIONS

INSTRUMENT CLUSTER (Figs.
50
thru
53)

Removal
and
Installation

1.
Disconnect battery ground cable.

2.
Remove mast jacket lower support screws
at toe
pan.

3.
Remove mast jacket upper support bolts
and
allow

steering wheel
to
rest
on
seat cushion.

CAUTION: Both supports must
be
detached
to

prevent distortion
of
mast jacket.

4.
Remove cluster attaching screws from face
of
panel

and partially remove assembly from console opening.

5. Reaching behind cluster assembly, disconnect speed-

ometer cable, speed warning device
(if so
equipped
-

Fig.
51) and
chassis harness connector
at
rear
of

panel.

6. Remove assembly from console opening to
a
suitable

bench area
for
required service operations.

7.
To
install, reverse removal procedure.

INSTRUMENT CLUSTER LAMP REPLACEMENT

1.
Turn bulb holder counterclockwise
and
pull
out to

remove from
the
cluster housing.
2.
Pull bulb straight out
to
remove from socket.

3.
Press replacement bulb inward
to
lock
in
socket.

4.
Insert lamp assembly into housing, with lugs
on

holder entering notches
in
housing,
and
turn clock-

wise
to
lock
in
place.

PRINTED CIRCUIT REPLACEMENT

1.
Remove instrument cluster
as
previously described

in this section.

2.
Remove
all
cluster illuminating and indicator lamps

from housing.

3.
Remove fuel gauge terminal nuts
or
tachometer
re-

taining nuts securing printed circuit
to
housing.

4.
Remove four
hex
head screws retaining printed
cir-

cuit
to the
cluster housing
and
remove circuit from

housing.

5.
To
install, reverse removal procedure.

CAUTION:
The
retaining screws
are
part
of

the grounding circuit
and
must
be
installed
to

provide proper connections
for the
printed
eir-

cuit.

CHEVROLET CHASSIS SERVICE MANUAL

ELECTRICAL-BODY AND CHASSIS 12-42

Fig.
57 - Tilt Steering Column

12.
Remove upper support bracket bolts and bracket

assembly.

CAUTION: Do not suspend column by lower

reinforcement only.

Reinforce column and remove wiring harness pro-

tector and clip, then position bracket and reinstall

bolts (finger tight).

13.
Remove shift lever bowl from mast jacket and dis-

engage from wiring harness.

14.
Remove three mounting screws from engagement

with lockplate. Use care not to lose 3 springs as

screws are removed.

15.
Disassemble switch and upper bearing housing from

switch cover.

NOTE:
Directional switch is not repairable

and must be replaced.

16.
Insert the upper bearing housing assembly and signal
switch assembly into, the cover, feeding the signal

switch wires through the. cover.

17.
Align signal switch and bearing housing holes with

holes in the cover. Install three mounting screws

through the holes.

18.
Slide three springs on to screws and place lockplate

in position over screws and springs. Tighten screws

three turns into lockplate.

19.
Feed switch wire through the shift lever bowl and

place upper end assembly on top of bowl.

20.
Place shift lever bowl and signal switch assembly

on top of jacket, aligning the tangs on the I.D. of the

lockplate with slots in jacket. Lock upper end of

assembly into position by pushing down on cover

assembly and rotating fully clockwise.

21.
Tighten 3 turn signal mounting screws.

22.
Remove mast jacket support clamp, position wiring

and install wiring cover and clip, then reinstall mast

jacket mounting bracket assembly.

Fig.
58 - Telescoping Column

CHEVROLET CHASSIS SERVICE MANUAL

ELECTRICAL-BODY AND CHASSIS 12-43

23.
Install
MCtT
ring over steering shaft using snap ring

installer J-22659 (refer to Section 9).

NOTE: Be sure retaining ring is completely

seated into groove.

24.
Install dial pointer on Chevrolet and Chevelle models

equipped with automatic transmission (if applicable).

25.
Install dial indicator and lamp assembly on Camaro

and Chevy n models equipped with automatic

transmission.

26.
Install mast jacket lower trim covers (if applicable).

27.
Install hazard warning knob and turn signal lever.

28.
Install shift lever.

29.
Install steering wheel.

30.
Install multiple connector to switch wiring using old

harness for wire color guide and connect to body

harness connector.

31.
Connect battery ground cable and check operation of

assembly.

Tilt Steering Column (Fig. 57)

Chevrolet, Chevelle and Camaro

1.
Disconnect battery ground cable.

2.
Disconnect directional switch wiring harness from

body harness at multiple connector under instrument

panel.

3.
Remove steering wheel assembly (refer to Steering,

Section 9).

4.
Remove preload spring and cancelling cam from end

of shaft.

5.
Remove shift lever pin and lever from steering col-

umn (except floor shift).

6. Remove directional le*ver screw and lever.

7.
Push in hazard warning knob and unscrew knob.

8. On Camaro models equipped with automatic trans-

mission, remove quadrant dial and lamp assembly

from column.

9. Remove mast jacket trim cover
(s).

10.
On Chevrolet and Chevelle models with automatic

transmission, loosen set screw and remove quadrant

dial pointer.

11.
Assemble slide hammer Tool J-6585-1 to turn signal

cover remover Tool J-21486. Place cover remover

over turn signal cover, tighten clamp, and pull cover

from end of column with slide hammer (Refer to

Steering, Section 9).

12.
Remove three switch mounting screws, noting short

length of top screw.

13.
Cut multiple connector from switch wiring and slide

switch from end of column.

14.
To install new switch, feed wiring through the bear-

ing housing, around support, and through shift bowl

and shroud.

15.
Feed through wiring protector. If clearance is not

sufficient loosen mast jacket bracket retaining bolts.

16.
Insert switch wiring terminals in multiple connector.

Use old connector
and
wiring for color guide.
17.
Position switch and install three mounting screws

with short screw in top position.

18.
Be sure hazard warning switch is pushed in, then

install turn signal cover using special Tool J-21853.

On automatic columns align key in cover with keyway

in bearing housing.

19.
Install turn signal lever, hazard warning knob and

tilt lever.

20.
Install shift lever and roll pin (where applicable).

21.
Install dial pointer on Chevrolet and Chevelle. On

Camaro install dial indicator and lamp assembly.

22.
Install trim covers and retaining screws.

23.
Install cancelling cam and preload spring.

24.
Install steering wheel (Refer to Section 9).

25.
Connect switch wiring to body harness under instru-

ment panel.

26.
Connect battery ground cable and check operation of

unit.

Standard and Telescoping Steering Column

Corvette (Fig. 58)

1.
Disconnect battery ground cable.

2.
Disconnect signal switch harness wiring from chas-

sis wiring harness at multiple connector under in-

strument panel.

3.
Remove steering wheel assembly as outlined in

Steering, Section 9.

4.
Remove preload spring and cancelling cam.

5.
Remove directional signal lever screw and lever.

6. Push in hazard warning knob, unscrew and remove

knob.

7.
Remove lower trim cover retaining screws and

cover.

8. Remove retaining ring, thrust and wave washers

from upper end of shaft.

9. Cut wiring above connector.

10.
Remove three switch mounting screws, slide switch,

cover and upper bearing housing from column, pull-

ing wire through protector and escutcheon.

11.
To install replacement switch, assemble upper bear-

ing housing and turn signal switch into switch cover,

then feed wiring through escutcheon and protector

until switch can be positioned on mast jacket.

12.
With switch positioned on mast jacket, install three

switch mounting screws.

13.
Install thrust and wave washers and snap lock ring

in place.

14.
Install turn signal lever and hazard warning knob.

15.
Install cancelling cam and upper bearing preload

spring on steering shaft.

16.
Install steering wheel assembly.

NOTE:
Be sure directional signal switch is in

neutral position before installing wheel.

17.
Install connector on directional signal wiring har-

ness and connect to body harness connector.

CHEVROLET CHASSIS SERVICE

BUMPERS 14-3

required to position the bumper at the correct

mounted height. ,

3.
Tighten all mounting bolts securely and connect li-
cense plate lamp wiring. On Caprice models, con-

nect back-up lamp wiring. Lower vehicle.

GENERAL DESCRIPTION-CHEVELLE

The new front bumper is of a one piece design with the

parking and turn signal lamp assemblies attached to each

outboard end of the bumper.
The rear bumper is also of a one piece design with

provisions for rear gas fill. The back-up lamp assem-

blies are attached near the center of the bumper.

SERVICE OPERATIONS

FRONT BUMPER ASSEMBLY

Removal

1.
Raise and support front of vehicle.

2.
Disconnect parking lamp wiring. -

Fig.
3 - Front Bumper Assembly - Chevelle

Disassembly

1.
Remove bolts attaching braces and brackets to

bumper.

2.
Remove bolts from each parking lamp assembly and

remove parking lamps from bumper.

Assembly

Attach both parking brake lamp assemblies to front

bumper and tighten bolts firmly. Assemble the front

bumper parts by following the disassembly procedure in

reverse order. Except for the parking lamp attachments,

install all bolts loosely; do not tighten any bolts until all

bolts are installed.

Installation

1.
Position the front bumper on the frame horns align-

ing holes in brackets and braces with those in the

frame.

2.
Loosely install bolts, lock washers, and nuts. Note

that eight sided adjustment washer (fig. 3) is placed

in the tab of each mounting bracket. Dial tjie adjust- .

ment washers in the tabs as required to position the

bumper at the correct mounted height.

3.
Tighten all mounting bolts securely, connect the

parking lamp wiring, and lower front of vehicle.
3.
Remove bolts retaining the bumper brackets and

braces to the frame.

4.
Remove bumper assembly from vehicle.

ADJUSTMENT

WASHER

Fig.
4-Rear Bumper Assembly - Chevelle

REAR BUMPER ASSEMBLY (Fig. 4)

Removal

1.
Raise rear end of vehicle.

2.
Disconnect rear license plate lamp and back-up lamp

wiring.

3.
Remove bolts, located behind license plate door, at-

taching face bar reinforcement to frame.

4.
Remove four bolts retaining bumper brackets and

braces to frame.

5. Remove bumper from vehicle.

Disassembly

1.
Remove license plate lamp and back-up lamps from

bumper.

2.
Remove brackets and braces at each end of bumper.

3.
Remove license plate door.

4.
Remove rivets attaching bracket at center of bumper.

Assembly

Attach license plate lamp and back-up lamp assemblies

to bumper; tighten bolts firmly. Assemble the bumper

parts by following the disassembly procedure in the re-

verse order. Except for the license plate lamp and back-

up lamp attachments, install all bolts loosely; do riot

CHEVROLET CHASSIS SERVICE MANUAL

BUMPERS 14-4

tighten any bolts until all bolts have been installed.

Installation

1.
Position bumper bracket and brace on the frame

aligning holes in frame with those in bracket and

brace.

2.
Loosely install bolts, lock washers and nuts. Note
that eight sided adjustment washers (fig. 4) are

placed at the inside surface of each rear frame

channel. Dial washers as required to position

bumper at correct height.

Tighten all mounting bolts securely, connect back-up

lamp and license plate lamp wiring, and lower rear

of vehicle.

GENERAL DESCRIPTION-CHEVY II

The front and rear bumpers are of a one piece design

with the parking and turn signal assemblies attached to

each outboard end of the front bumper.

SERVICE OPERATIONS

FRONT BUMPER ASSEMBLY (Fig. 5)

Removal

1.
Raise front end of vehicle.

2.
Disconnect parking lamp wiring.

3.
Remove bolts retaining bumper brackets and braces

to frame.

4.
Remove bumper assembly from vehicle.

Disassembly

1.
Remove bolts securing parking lamp assemblies and

remove parking lamps from vehicle.

2.
Remove bolts attaching braces and bumper brackets

to bumper face bar.

Assembly

Referring to Figure 5, assemble brackets and braces

and install parking lamps to face bar. Install all bolts

loosely—do not tighten any bolts until all bolts have been

installed.

Installation

1.
Position assembled bumper on frame extensions,

aligning holes in extension with holes in brackets and

braces.

2.
Install bolts, lock washers, and nuts; tighten

securely.
3.
Connect parking lamp wiring and lower front end of

vehicle.

REAR BUMPER ASSEMBLY (Fig. 6)

Removal

1.
Disconnect license plate lamp wire at connector.

2.
Raise vehicle from floor. From forward side and

underside of rear crossmember, remove mounting

bolts retaining the bumper brackets to the vehicle.

3.
Remove bumper assembly from vehicle.

Disassembly

1.
Remove license plate lamp.

2.
Remove, bolts attaching each bracket to bumper.

Check condition of seal; replace if necessary.

Assembly

1.
Position brackets on face bar as shown in Figure 6

and install mounting bolts; tighten nuts securely.

2.
Install license plate lamp.

Instalfation

1.
Position bumper assembly on vehicle, aligning tapped

holes in bracket with- slotted holes in rearward face

of rear crossmember and install bolts loosely.

2.
Align slotted hole in bracket with tapped hole in

lower flange of rear crossmember and install bolt

loosely.

3.
Adjust entire bumper assembly so that the distance

Fig.
5 - Front Bumper Assembly - Chevy
Fig.
6 - Rear Bumper Assembly - Chevy

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES 15-2

GENERAL DESCRIPTION

The Cruise Master is a speed control system which

employs engine manifold vacuum to power the throttle

Servo unit. The Servo moves the throttle when speed

adjustment is necessary by receiving a varying amount

of bleed air from the Regulator unit. The Regulator

varies the amount of bleed air through a valve system

which is linked to a speedometer-like mechanism. The

speedometer cable from the transmission drives the

Regulator, and a cable from the Regulator drives the

instrument panel speedometer. The. engagement of the
Regulator unit is controlled by an Engagement Switch

located at the end of the turn signal lever. Two brake

release switches are provided: an Electric Switch dis-

engages the Regulator unit and a Vacuum Switch de-

creases the vacuum in the Servo unit to quickly return

the throttle to idle position.

The operation of each unit of the system and the

operation of the entire system under various circum-

stances is described below. Figure 1 shows the location

of the system components within the vehicle-

COMPONENT OPERATION

ENGAGEMENT SWITCH

This switch, located within the turn signal knob, has

three positions. In the fully released position, the switch

passes current through resistance wire to effect a "hold

in" magnetic field in the Regulator solenoid. This cur-

rent is sufficient only to hold the solenoid in place once

it has been actuated by the "pull in" circuit. Depressing

the button partially allows current to flow to the Regu-

lator solenoid at full voltage which causes the solenoid

to pull in. Depressing the button fully opens the circuit

to both the resistance and standard solenoid feed wires

and the solenoid becomes de-activated.

During vehicle operation the three switch positions

have the following functions:

Released

a. System not engaged: No function of the system

will occur although a small current is flowing

through the solenoid via the resistance wire (at

vehicle speeds over 20 mph).

b.
System engaged: The small current flowing

through the resistance wire is holding the solenoid

in the engaged position.

^r-WIRE RELIEF LUG

1 ^-#2-BLUE WIRE

L'3.BLACK WIRE
X /-TURN SIGNAL LEVER

SWITCH—^
^SN

RETAINING RING-^ %^

BUTTON -^

Fig.
2 - Cruise Master Engagement Switch
Partially Depressed

Full voltage is applied to the solenoid (vehicle speed

over 20 mph) which sets the Regulator to maintain the

vehicle speed at the time of Regulator engagement.

Fully Depressed

No electricity flows to the solenoid and the Regulator

is inactive. This position is used by the driver when he

desires to raise or lower his controlled speed. He may

accelerate to his new speed, press the button fully (Regu-

lator releases previously set speed) and release the but-

ton. Upon releasing the button, it passes through the

partially depressed position and the solenoid is "pulled

in", then into released position which provides "hold in"-

current. The driver may also press the button fully with

no pressure on the accelerator pedal. In this case the

regulator releases control of the throttle which returns

to idle and the car slows. When the button is released

the solenoid is pulled in and held in respectively and the

regulator resumes speed control at the speed of the

vehicle during the moment of button release (at vehicle

speeds over 20 mph).

LOCK
NUT

ORIFICE
TUBE

AND
CONNECTOR

ASSEMBLY

AIR FILTER AND

SOLENOID HOUSING COVER

Fig. 3 - Regulator Unit

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES 15-7

6. The car begins to descend a hill--car speed in-

creases slightly and the regulator movements oc-

curing above occur again except in reverse. The

rubber drum is turned further against spring tension

and the air bleed orifices are uncovered more. This

bleeds more air to the Servo reducing the vacuum in

the unit. The diaphragm moves away from the

vacuum port, closes the throttle slightly, and with-

draws the tapered needle from the vacuum orifice.

With the orifice enlarged, the increased vacuum

counteracts the increased air bleed and the dia-

phragm finds a balance again at a reduced throttle

opening.

7.
Driver accelerates by pressing accelerator pedal-

car speed increases and the system responds by

moving the diaphragm to decrease throttle opening.

Since a bead chain is used, the chain merely relaxes

and has no effect on throttle operation. After the

driver releases pressure from the pedal, the throttle

will close until car speed decreases to the pre-set

speed. At that point the Regulator bleeds less air

to the Servo which opens the throttle enough to

maintain the pre-set speed. The system returns to a

stable condition.

8. Driver desires higher controlled speed, presses ac-

celerator until new speed is reached, and depresses

Engagement Switch fully and releases button--speed

sensing assembly tries to turn in a direction that

would decrease the throttle opening until the driver

fully depresses the Engagement Switch. Then the

current is cut off to the solenoid which retracts; the

solenoid nose expands the "U" clip releasing its

grip on the rubber drum. The drum and disk as-

sembly then rotates to a new position because of the

higher car speed. When the solenoid retracts, it also

shuts off vacuum to the Servo and opens the vacuum

port to atmospheric pressure within the Regulator

thereby bleeding down the Servo toward idle throttle

position. As the driver releases the Engagement

Switch, the contacts cause "pull in" and "hold in" of

the solenoid respectively. The system is engaged to
maintain the car speed at the time of Engagement

Switch release.

9. Driver desires lower cruising speed, presses En-

gagement Switch fully, waits until car speed de-

creases to desired speed then releases Switch--when

the Engagement switch is fully depressed the sole-

noid is de-energized causing the vacuum switch to

bleed down the Servo to idle throttle position and the

"U"
clip of the idle bleed valve is released from the

rubber drum. The drum and disk assembly is free

to rotate to a position which corresponds to vehicle

speed as the car slows. When the driver releases

the Engagement Switch, the unit "pulls in" and "holds

in" in the normal manner. The air bleed valve is

clutched to, the rubber drum at the car speed during

switch release. Vacuum is again applied to the

Servo and throttle control is assumed by the Regu-

lator to maintain the car speed at the time of switch

release.

10.
With system in operation, driver applies brakes--

simultaneously the Vacuum Release and Electric

Release Switches operate. The Vacuum Switch

bleeds air into the Servo through the air bleed line

coming from the Regulator. The vacuum is reduced

in the Servo and the throttle returns to idle position.

The Electric Release Switch cuts off power to the

entire system and the solenoid is de-energized. If

the driver removes his foot from the brake pedal the

Electric Switch again feeds voltage to the Engage-

ment Switch and the Vacuum Switch seals the air

bleed line. If the vehicle speed is above 20 mph

when this occurs, reduced voltage will flow to the

solenoid through the 40 ohm wire which will not be

sufficient to "pull in" the unit. If vehicle speed is

below 20 mph no current will flow since the tang

on the rubber drum has opened the low limit switch

points in the Regulator. In either case, after de-

pressing the brake pedal, the system will not con-

trol car speed until the driver operates the engage-

ment switch above 20 mph.

SERVICE OPERATIONS

The components of the Cruise Master system are de-

signed to be replaced should they become inoperative.

The Regulator is calibrated in such a manner during

manufacturing that overhaul operations are impractical.

However, one adjustment may be made to the Regulator to

correct speed drop or increase at the time of

engagement.

BRAKE RELEASE SWITCHES

ELECTRIC

Service — An inoperative switch must be replaced.

Switch replacement is identical to standard brake lamp

switch replacement.

Adjustment- The brake switch plunger must clear the

pedal arm when the arm is moved 1/4 inch measured at

the switch (Figure 7).

VACUUM

Service
—
An inoperative (sticking, plugged, or leaking)

switch must be replaced. Switch replacement is similar
to brake switch replacement. Be certain that the hose to

the switch is connected firmly and is not cracked or

deteriorated.

Adjustment- The brake switch plunger must clear the

pedal arm when the arm is moved 5/16 inch measured at

the switch (Figure 7).

ENGAGEMENT SWITCH

Service

replacement.
The engagement is serviced only by

Removal

1.
Pry the engagement button out of the turn signal knob

with a small thin bladed screwdriver (Figure 2).

2.
With a small hook or long nosed pliers, remove the

switch retaining ring.

3.
.Pull switch outward utilizing the slack in the wiring

harness.

4.
With a small soldering iron, unsolder the wires and

resolder them to the correct terminals of the re-

placement switch.

CHEVROLET CHASSIS SERVICE MANUAL

ACCESSORIES
15-8

BROWN
BRAKE

SWITCH

+12V *

BLACK
CONNECTOR

AT FUSE BLOCK

CRUISE POSITION

BUTTON RELEASED

ENGAGE POSITION

BUTTON PARTIALLY DEPRESSED^ N. ENOAOi SWITCH

TRIM POSITION N. N. I

BUHON FULLY DEPRESSED. \ ^

BROWN

BLUE

ENGAGE SWITCH

CONFIGURATION

BLACK

BLUE

REGULATOR
- SOLENOID COIL

(5 a RESISTANCE)
9 BLACK

BLUE

REGULATOR

Fig.
10 - Wiring Diagram

Replacement

1.
Insert the switch into the turn signal knob, push the

retaining ring firmly against the switch, and push the

operating button onto the switch plunger. " .
SERVO

Service
—
H the Servo unit is found to be defective, re-

placement is required. Note the condition of the hoses

and replace any which are cracked or deteriorated.

CHEVROLET CHASSIS SERVICE MANUAL