BRAKES
SECTION 5
CONTENTS OF THIS SECTION
Duo Servo Brakes
Disc Brakes
Page
5-1 Power Brakes
5-24 Special Tools
Page
5-31
5-32
DUO-SERVO BRAKES
INDEX
Page
General Description 5-1
Maintenance and Adjustments 5-3
Hydraulic Brake Fluid .. . 5-3
Bleeding Hydraulic System 5-3
Pressure Bleeding 5-3
Manual Bleeding 5_4
Push Rod to Main Cylinder Clearance 5-5
Hydraulic Brake Lines 5-5
Hydraulic Brake Hose 5-5
Hydraulic Brake Tubing 5-6
Brake Adjustment. .................... 5-7
Service Brake 5-7
Parking Brake 5-8
Component Replacement and Repairs 5-9
Parking Brake - Chevrolet, Chevelle and
Camaro 5^9
Pedal Assembly 5-9
Front Cable ,. . . 5-9
Center Cable 5-9
Rear Cables. . 5-9
Parking Brake - Chevy n 5-9
Lever Assembly 5-9
Idler Lever 5-11
Front Cable 5-11
Rear Cable . . ; 5-12
Parking Brake - Corvette 5-13
Lever Assembly . . . . 5-13
Front Cable 5-14
Rear Cable . . 5-14
Brake Pedal 5-15
Shoes and Linings 5-16
Organic 5-16
Metallic 5-17
Main Cylinder 5-18
Wheel Cylinders 5-21
Anchor Pin 5-22
Front Wheel 5-22
Rear Wheel 5-22
Brake Drums • 5-22
Brake Pipe Distribution and Switch Assembly . . . . . 5-23
Camaro Pressure Regulator Valve 5-23
GENERAL DESCRIPTION
All 1967 models are equipped with a new split brake
system as a safety feature. If a wheel cylinder or brake
line should fail at either the front end or rear end of
the vehicle, the operator can still bring the vehicle to
a controlled stop. The system is designed with separate
hydraulic systems for the front and rear brake using
a dual master cylinder (fig. 1). The design of the master
cylinder is similar to that used on the 1966 Corvette
in that it has two entirely separate reservoirs and outlets
in a common body casting. The front reservoir and outlet
is connected to the front wheel brakes, and the rear
reservoir and outlet is connected to the rear wheel
brakes. Two pistons within the master cylinder receive
mechanical pressure from the brake pedal push rod and
transmit it through the brake lines as hydraulic pressure
to the wheel cylinders. The filler cap is accessible from
inside the engine compartment.
A new brake pipe distribution and switch assembly
is mounted below the main cylinder. The front and rear
hydraulic brake lines are routed from the main cylinder,
through the brake pipe distribution and switch assembly,
to the front and rear brakes as shown in Figure 2. The
switch is wired electrically to the brake alarm indicator
light on the instrument panel. In the event of fluid loss
in either the front or rear brake system the indicator
on the instrument panel will illuminate red. (The indi-
cator will also' be illuminated when the parking brake is
applied.)
On Camaro models equipped with air conditioning, the
rear brake hydraulic line is routed through a pressure
regulator valve mounted on the left frame side rail
(fig. 3). The valve controls the hydraulic pressure to
the rear brakes resulting in the correct pressure balance
between the front and rear hydraulic systems.
The self-adjusting brakes (fig. 4), used on both front
and rear of all models, are the Duo-Servo single anchor
type which utilize the momentum of the vehicle to assist
in the brake application. The self-energizing or
self-
actuating force is applied to both brake shoes at each
wheel in both forward and reverse motion. The brake
shoe linings are bonded to the shoes.
Wheel cylinders are the double piston type permitting
even distribution of pressure to each brake shoe. To
keep out dust and moisture, both ejads of each wheel
cylinder are sealed with a rubber booC The wheel
cylinders have no adjustments.
The Chevrolet, Chevelle, and Camaro parking brakes
have a foot operated ratchet type pedal mounted to the
left of the steering column. A cable assembly connects
the pedal to an intermediate cable by means of an equal-
izer, where the adjustment for the parking brake is
incorporated. The intermediate cable attaches to the
CHEVROLET CHASSIS SERVICE MANUAL
BRAKES
5-3
PRIMARY
SHOE
PAWL
WIRE LINK
OVERRIDE
LEVER
VERRIDE
SPRING
RETURN
SPRING
STAR
WHEEL
Fig.
3—Camaro
Pressure
Regulator
Valve
Fig.
4-Self-Adjusting
Brake
MAINTENANCE AND ADJUSTMENTS
In any service operation it is extremely important
that absolute cleanliness be observed. Any foreign matter
in the hydraulic system will tend to clog the lines, ruin
the rubber cups of the main and wheel cylinders and
cause inefficient operation or even failure of the braking
system. Dirt or grease on a brake lining may cause
that brake to grab first on brake application and fade
out on heavy brake application.
The split system consists basically of two separate
brake systems. When a failure is encountered on either,
the other is adequate to stop the vehicle. If one system
is not functioning, it is normal for the brake pedal lash
and pedal effort to substantially increase. This occurs
because of the design of the master cylinder which
incorporates ah actuating piston for each system. When
the rear system loses fluid and takes in air, its piston
will bottom against the front piston. When the front
system loses fluid and takes in air, its piston will
bottom on the end of the main cylinders body. The loss
of fluid in one of the systems causes an uneven hydraulic
pressure balance between the front and rear systems.
The brake pipe distribution and switch assembly, near
the main cylinder, detects the loss of pressure and il-
luminates the brake alarm indicator light on the instru-
ment panel. The pressure loss is felt at the brake pedal
by an apparent lack of brakes for most of the brake
travel and then, when failed chamber is bottomed, the
pedal will harden.
HYDRAULIC BRAKE FLUID
Use GM Hydraulic Brake Fluid, Supreme No. 11 or
equivalent when servicing brakes. This brake fluid is
satisfactory for any climate and has all the qualities
necessary for proper operation, such as a high boiling
point to prevent vapor lock and the ability to remain
fluid at low temperatures.
In the event that improper fluid has entered the system,
it will be necessary to service the system as follows:
1.
Drain the entire system.
2.
Thoroughly flush the system with clean alcohol,
188
proof,
or a hydraulic system cleaning fluid
such as "Declene".
3.
Replace all rubber parts of the system, including
brake hoses.
4.
Refill the system.
5. Bleed the system.
BLEEDING HYDRAULIC SYSTEM
The hydraulic brake system must be bled whenever
any line has been disconnected or air has in some way
entered the system. A ''spongy" pedal feeling when the
brakes are applied may indicate presence of air in the
system. The system must be absolutely free of air at
all times. Bleeding should be done on the longest line
first; the proper sequence to follow is left rear, right
rear, right front, and left front (fig. 5). Bleeding of
brake system may be performed by one of two methods—
either pressure or manual.
PRESSURE
BLEEDING
1.
Clean all dirt from top of main cylinder and remove
cylinder cover and rubber diaphragm.
2.
Reduce fluid level in main cylinder until reservoirs
are approximately half full.
NOTE:
Make sure brake fluid in bleeder equip-
ment is at operating level and that the. equipment
is capable of exerting 30 to 50 lbs. hydraulic
pressure on the brake system.
3.
Install brake bleeder adapter J-22489 (fig. 6) on
main cylinder. Connect hose from bleeder equipment
to bleeder adapter and open release valve on bleeder
equipment.
CHEVROLET CHASSIS SERVICE MANUAL
Installation
1.
Pass end of cable and conduit tip through flange
plate entry hole, making sure that conduit locking
fingers all expand fully.
2.
Compress retaining spring and place cable end in
actuating lever.
3.
Install secondary shoe hold-down pin and spring.
4.
Install secondary shoe return spring.
5. Install drum and wheel.
6. Snap cable conduit into spring clip at shock ab-
sorber lower mount.
7. Install cable conduit in bracket at center body bump-
er bracket.
8. Position cable conduit ends in cable bracket and
install retainers in grooves.
9. Place equalizer on cable and insert forward cable
stud. Install check nut and return spring.
NOTE:
To perform its intended function, equal-
izer must be free to slide on rear cable. Lubri-
cate cable at equalizer with chassis grease.
10.
Adjust rear service brakes and parking brake as
outlined in this section.
BRAKES 5-13
PARKING BRAKE-CORVETTE (Fig. 22)
Lever Assembly
Removal
1.
Place parking brake lever in the fully released
position.
2.
Under vehicle, unhook and remove return, spring.
3.
Remove rear nut from cable stud at equalizer and
allow front cable to hang down.
4.
Inside vehicle, remove six screws securing cover
to underbody. It is necessary to push the seat
cushion down as shown in Figure 23 to gain access
to the lower mounting screw on each side. Remove
the retainer. Lift the cover upward and to the
rear to allow seal to slide out of cover slot and
remove cover.
5. Remove trim seal from lever (fig. 24).
6. Remove screw and washer securing parking brake
alarm switch to side of lever assembly.
7. Remove four bolts securing lever assembly to under-
body and lift lever assembly upward. Remove lever
forward mounting bracket.
Fig.
22—Parking Brake System—Corvette
CHEVROLET CHASSIS SERVICE MANUAL
BRAKES 5-14
Fig.
23—Removing or Installing Cover Lower Mounting Screws
Fig.
24—Removing or Installing Trim Seal
8. Remove front cable from lever assembly using long
nose pliers as shown in Figure 25. Remove lever
from vehicle.
Installation
1.^
Install front cable in lever assembly using long
nose pliers as shown in Figure 25. Slide slack
cable through hole and place lever assembly in
position.
2.
Place forward mounting bracket in position and
secure plate and lever assembly to underbody with
four mounting bolts.
3.
Secure parking brake alarm switch to side of lever
assembly with washer and screw (fig. 24).
4.
Install trim seal on lever (fig. 24).
5. Insert the end of the trim seal into the slot in the
cover and slide the cover forward and down into
position.
6. Place the retainer in position. Secure retainer and
cover to underbody with six screws. It is necessary
to push the seat cushion down as shown in Figure 23
to gain access to the lower mounting screw hole on
each side.
7. Under vehicle, insert front cable stud through equal-
izer assembly and secure with nut.
8. Install return spring.
9. Adjust parking brake as outlined under Maintenance
and Adjustments in this section.
Front Cable
Removal
1.
Perform the complete parking brake lever removal
procedure above.
2.
Under vehicle, remove nut, washer, and bolt se-
. curing pulley to pulley bracket (fig. 22).
3.
Remove seal grommet from underbody cable hole.
4.
Pull front cable out of vehicle.
Installation
1.
Install seal grommet around front cable.
2.
Slide front cable into position through cable hole
and work seal grommet into installed position.
3.
Under vehicle, loop front cable around pulley wheel
and secure pulley wheel to bracket with bolt, washer,
and nut (fig..22).
4.
Perform the complete parking brake lever installa-
tion procedure above.
Removal
1.
Remove the cable clip retainers on the back side of
the frame rail from each of the rear brake cable
ends.
2.
Disconnect the cable at the rear wheel flange plate.
3.
Remove the cable ball out of the recess in .the brake
lever assembly clevis.
4.
Disconnect the cables at the equalizer connector and
remove the cables.
Installation
1.
Attach the rear cable balls on the rear cable ends
to the rear wheel recess in the brake lever assembly
clevis.
2.
Attach the cable assembly to the rear wheel flange
plate.
3.
Connect the cable assemblies along the frame rail
area.
4.
Insert the cable end through the equalizer and attach
to the equalizer connector.
5. Adjust as outlined under Maintenance and
Adjustments.
6. Lubricate the cables and all moving parts for
trouble-free operation—see Lubrication, Section 0.
Fig.
25—Removing or Installing Front Cable
CHEVROLET CHASSIS SERVICE MANUAL
SECTION 12
ELECTRICAL-BODY AND CHASSIS
CONTENTS
OF
THIS
SECTION
Page
Page
System 12-1
Instruments and Gauges 12-21
Directional Signal 12r40
Windshield Wipers and Washers 12-44
Wiring Diagrams 12-56
Special Tools 12-60
LIGHTING SYSTEM
INDEX
Page
General Description
!2-i
Maintenance and Adjustments
•.................. 12-2
Headlamp Adjustment......................
12-3
Headlamp Panel Travel Adjustment.
12-5
Service Operations.
. . .. 12-5
Front Lighting
12-5
Headlamp
. 12_5
Parking Lamp
12-5
Fender Lamp
. 12_^
Headlamp Panel
12-8
Headlamp Panel Motor
^2-9
Rear Lighting
l2-10
Tail, Stop and Directional Lamps
12-10
Page
Backing Lamps
12-14
License Plate Lamp
12-14
Automatic Transmission Quadrant Lamp
12-14
Seat Separator Console Lamps
. 12-15
Lighting Switch
. . 12-15
Wiper Switch.
12-15
Stoplight Switch
12-15
Dimmer Switch
12-15
Backing Lamp Switches
12-15
Neutral Safety Switches
12-17
Parking Brake Alarm Switch
................. 12-19
Instrument Panel Compartment Lamp/Switch
12-19
Cirgarette Lighter
12-19
GENERAL DESCRIPTION
.
The lighting system includes: the main lighting switch,
stop light, dimmer, and backing lamp switches, head-
lamps, parking lamps, stop, tail and directional lamps,
instrument illumination and indicator lamps, and the
necessary wiring to complete the various circuits. A
fuse panel provides convenient power take offs and fuse
clips for the appropriate circuits (fig. 1).
Chevrolet and Chevelle headlamp installation is all
new in that the headlamps are located in the radiator
support with adjusting screws and springs. Eliminating
the need for having separate headlamp housings. Chev-
rolet and Chevelle headlamp retainers and springs are
interchangeable.
Chevy n headlamp housings are new because of revised
front end styling and Corvette front end lighting is basi-
cally carryover.
Front fender lamps have been added as an option for
Chevrolet models and as standard equipment on Caprice
series.
Camaro models use single headlamps and the Rally
Sport model headlamps are covered by a retractable
section of the grille when lamps are not used. The sec-
tion of the grille covering the headlamps folds back when
lights are required; the headlamps are stationary. The
covering is retracted by a small electric motor mounted
to the headlamp housing. The headlamps are automat-
ically uncovered when the headlight switch is pulled "ON"
for illumination. If at any time the electrical circuit
becomes inoperative, the lamps can be uncovered manu-
ally. The ignition switch must be
"ON"
in order to close
the headlamp doors.
Parking lamp for Chevelle and Chevrolet models are
new due to revised front end sheet metal and bumper
styling. Parking lamps are located in the bumper on
Chevrolet, Chevelle and Chevy n models
Camaro parking lamps are located in the radiator
grille except for the Rally Sport models on which the
parking lamps are in the valance panel. For styling
reasons, the lens is white and an amber glass bulb is
used. All Camaro parking lamps require a separate
ground wire to assure a good ground contact because of
the plastic grille and painted contact surfaces.
The Chevrolet tail, stop, and directional lamps are in
one housing with a three section lens design on Impala
and Caprice sedans. The center lens for Impala series
is the back-up lamp. The center lens on the Caprice is
a tail lamp with the back-up lamps being located in the
rear bumper. Chevrolet station wagons have three indi-
vidual housings with three lenses, the center lamp being
the back-up. Biscayne and Bel-Air sedans have a single
housing and lens for tail, stop, and directional lamp with
a similarly constructed back-up lamp inboard and adja-
cent to it.
Chevelle tail, stop, and directional lamps are a single
lens design that follows through with the rear fender
styling. The back-up lamp is located in r.ear bumper.
Camaro models except Rally Sport have tail lamps
with integral back-up lamps mounted inboard of the rear
fenders between the trunk opening and bumper. The
Rally Sport model has dual tail lamps in the rear housing
and valance mounted back-up lamps.
Corvette, Chevy n, and Corvair tail and directional
signal lights are carryover. The Corvette has new back-
up lamps center mounted above the license plate opening.
CHEVROLET CHASSIS SERVICE
ELECTRICAL-BODY AND CHASSIS 12-19
VIEW A
•CONTACT SUPPORT
DRIVE SLOT IN LINE
WITH HOLE IN SWITCH
PAWL
CONTACT POINT B
CONTACT SUPPORT
DRIVE SLOT IN LINE
WITH HOLE IN SWITCH
FLOOR SHIFT
(EXCEPT CAMARO)
COLUMN SH
Fig.
31 - Neutral Safety Switches
PARKING BRAKE ALARM SWITCH REPLACEMENT
Corvette (Fig. 33)
1.
Remove seat belt retainer and parking brake cover
assembly from center console.
2.
Disconnect wire from brake alarm switch.
3.
Remove retaining screw and switch from
reinforcement.
4.
Position new switch to reinforcement and install re-
taining screw.
5. Connect switch wire and check operation of switch.
6. Install cover and seat belt retainer assembly.
Chevrolet, Chevelle, Chevy II and Camaro (Fig. 34)
1.
Disconnect wiring connector at switch terminal.
2.
Remove nut and lock washer or retaining bolt and
disengage switch from brace.
3.
To install, reverse removal procedure.
INSTRUMENT PANEL COMPARTMENT
LAMP/SWITCH REPLACEMENT
1.
Disconnect battery ground cable.
2.
Reach into glove box, depress bulb in end of switch
and turn counterclockwise to remove bulb.
3..
Remove switch from socket. Carefully detach wire
and terminal from switch.
NOTE:
On some model switches, the wire and
terminal cannot be detached from the switch
making it necessary to cut and splice the switch
wire.
4.
Insert wire and terminal into new switch.
5. Push switch into place and install bulb by setting it in
place, depressing and turning it clockwise.
CIGARETTE LIGHTER REPLACEMENT
Chevrolet, Chevy II, Camaro and Corvette (Fig. 23)
1.
Disconnect battery ground cable.
2.
Disconnect wire connector at rear of lighter unit
under dash.
3.
Remove retainer from rear of housing assembly and
disengage lighter unit from panel.
4.
To install, reverse removal procedure.
Chevelle (Fig. 35)
1.
Disconnect battery ground cable.
CHEVROLET CHASSIS SERVICE MANUAL
ELECTRICAL-BODY AND CHASSIS 12-20
Fig.
32 - Neutral Safety Switch — Corvette
Fig.
33 - Paricing Brake Alarip Switch — Corvette
CHEVROLET & CAMARO
CHEVELLE & CHEVY E
Rg.
34 - Parking Brake Alarm Switch Exc. Corvette
CHEVROLET CHASSIS SERVICE MANUAL
10
27
18
1.
To R. H. Door Jamb Switch
2.
To Inst. Pane! Compt. Light
3. To Heater Control
4. Heater Control Lamp
5. To Ignition Switch
6. To Seat Separator Harness Conn.
7. Inst. Cluster Conn.
8. To Directional Signal Conn.
9.
Door Jamb Switch to Light Switch Conn,
Fig.
40 - Instrument Panel Wiring
10.
To Wiper Switch
11.
To Light Switch Conn.
12.
To Gen. and Fwd. LP. Harness Asm,
13.
To Light Switch
14.
Courtesy Lamp
15.
To Dome Lamp Conn.
16.
ToL.H. Door Jam Switch
17.
Gen. and Fwd Harness Conn.
18.
To Paricing Brake Alarm Switch
19.
To Rear Door Jamb Switch
20.
To Fisher Body Conn.
21.
To Stop Lamp Switch
22.
To Back-Up Lamp Switch
23.
To Directional Signal Flasher
24.
To Cigarette Lighter
25.
To Heater Resistor
26.
Directional Signal Flasher
27.
Door Jamb Switch