1967 CHEVROLET CAMARO front brakes

BRAKES 5-27

CHEVELLE
, CHEVY II AND CAMARO SHOWN

1.
Caliper Belts

2.
Bleeder Valve

3. Caliper Half

4.
Piston Spring
Fig.
39-Caliper Assembly-Exploded View

5. Seal

6. Piston

7. Piston Boot

8. Brake Shoes
9. "O" Ri

10.
Caliper

11.
Retaining Pin

12.
Cotter Pin

caliper. Two retaining pins must be removed on

heavy duty Corvette front calipers. Identify the

inboard and outboard shoe if they are to be reused.

5. Remove the end of brake hose at bracket by re-

moving U-shaped retainer from the hose fitting and

withdrawing the hose from bracket.

6. Remove the caliper assembly from the mounting

bracket by removing two hex head bolts.

Disassembly (Fig. 39)

1.
Clean exterior of caliper with Declene, or equivalent.

On Chevrolet and Corvette front caliper, remove

brake hose.

2.
Separate the caliper halves by removing the two

large hex head bolts. Remove the two small "O"

rings from the cavities around the fluid transfer

holes in the two ends of the caliper halves.

3.
To free the piston boots so that the pistons may be

removed, push the piston down into the caliper

as far as it will go. Insert a screwdriver blade

under the inner edge of the steel ring in the boot,

and using the piston as a fulcrum, pry the boot from

its seat in the caliper
half.
CAUTION: Use care not to puncture seal when

removing pistons from caliper. ' ~

4.
Remove the pistons and piston springs from the

caliper
half.
Remove the boot and seal from their

grooves in the piston.

Cleaning and Inspection

1.
Clean all metal parts using Declene, or equivalent.

Remove all traces of dirt and grease. Do not use

mineral base solvents to clean brake parts.

2.
Using an air hose, blow out all fluid passages in the

caliper halves, making sure that there is no dirt

or foreign material blocking any of these passages.

3.
Discard all rubber parts. Boots, seals, and "O"

rings should be replaced with new service kit parts.

4.
Carefully inspect the piston bores in the caliper

halves. They must be free of scores and pits. A

scored or otherwise damaged bore will cause leaks

and unsatisfactory brake operation. Replace the

caliper half if either bore is damaged to the extent

that polishing with very fine crocus cloth will not

restore it.

CHEVROLET CHASSIS SERVICE MANUAL

BRAKES 5-28

Fig.
40—Installing Piston in Caliper Bore Using

Tool J-22591
Fig.
41—Installing Boot Seal in Caliper Bore

Using Tool J-22592

5.
Check the fit of the piston in the bore using a feeler

gage.
Clearance should be as follows:

2 1/16 inch Bore .0045 to .010

1 7/8 inch Bore .0045 to .010

1 3/8 inch Bore .0035 to .009

If the bore is not damaged, and the clearance exceeds

either of the upper limits, a new piston will be required.

Assembly

1.
Assemble the seal in the groove in the piston which

is closest to the flat end of the piston. The lip on

the seal must face toward the large end of the

piston. Be sure lips are in the piston groove and do

not extend over the step in the end of the groove.

2.
Place the spring in the bottom of the piston bore.

3.
Lubricate the seal with dean brake fluid.

4.
Install the piston assembly in the bore using appli-

cable piston rign compressor Tool J-22639, 22629

or 22591 as shown in Figure 40. Use care not to

damage the seal lip as piston is pressed past the

edge of the bore. .

5.
Assemble the boot in the groove of the piston closest

to the concave end of the piston. The fold in the boot

must face toward the end of the piston with the seal

on it.

6. Depress the pistons and check that they slide

smoothly into the bore until the end of the piston is

flush with the end of the bore. If not, re check piston

assembly and location of the piston spring and the

seal.

7.
Position applicable boot seal installer Tool J-22592,

J-22628, or J-22638 over the piston and seat the

steel boot retaining ring evenly in the counterbore

as shown in Figure 41. The boot retaining ring must

be flush or below the machined face of the caliper.

Any distortion or uneven seating could allow con-

taminating and corrosive elements to enter the bore.
8. Position the t:O}> rings in the small cavities around

the brake fluid transfer holes in both ends of the

outboard caliper halves. Lubricate the hex head

. bolts with Delco Brake Lube or clip in clean brake

fluid. Fit caliper halves together and secure with

bolts.
Refer to torque specifications in rear of

manual for correct torque valves.

Installation

1.
Carefully mount the assembled caliper over the edge

of the disc. Use a putty knife to depress pistons so

that the caliper can be lowered into position on the

disc (fig. 42). Use care to prevent damage to boots

• on the edge of the disc as the caliper is mounted.

2.
Secure the caliper to the mounting bracket with two

hex head bolts. Refer to torque specifications in

rear of manual for correct torque values.

CAUTION: If replacing old shoe assemblies,

be sure to get the shoes in the same position

from which they were removed. New shoe as-

semblies have an arrow printed on the back,

showing the direction of forward disc rotation.

3.
Install the shoe and lining assemblies as outlined in

this section.

4.
On Chevrolet and Corvette front calipers, place a

new copper gasket on the male end of the front

wheel brake hose. On all models, install brake hose

in the calipers. With the wheels straight ahead,

pass the female end of the brake hose through the

support bracket.

5.
Make sure the tube seat is clean and connect the

break line tube nut to the caliper. Tighten securely.

6. Allowing the hose to seek a normal position, without

twist, insert hex of the hose fitting into the 12-point

hole in the support bracket and secure it in place

with the "V"-shaped retainer. Turn the steering

geometry from lock to lock while observing the hose.

CHEVROLET CHASSIS SERVICE MANUAL

BRAKES 5-29

Fig.
42—Installing Caliper on Disc

Check that the hose does not touch other parts at

any time during suspension or geometry travel.

If contact does occur, remove the U-shaped retainer

and rotate the end of the hose in the support bracket

one or two points in a direction which will eliminate

hose contact. Reinstall the retainer and recheck

for hose contact. If it is satisfactory, place the

steel tube connector in the hose fitting and tighten

securely.

If rear brake caliper is being serviced, connect

brake line to caliper.

Bleed brakes as outlined in this section.

Install wheels and lower vehicle.

BRAKE DISC

Servicing of the disc brakes is extremely critical

due to tolerances required in machining of the brake

disc to insure proper brake operation. In manufacturing

the brake disc, tolerances of the rubbing surfaces for

flatness is .001 and for parallelism is .0005, while

lateral runout of the faces must not exceed .004 total.

The maintenance of these close controls of the shape of

the rubbing surfaces is necessary to prevent brake

roughness. In addition, the surface finish must be non-

directional and maintained at 30-50 micro-inches. This

control of the rubbing surface finish is necessary to

avoid pulls and erratic performance and promote long

lining life and equal lining wear of both left and right

brakes.

tight scoring of the disc surfaces not exceeding .015

in depth, which may result from normal use, is not

detrimental to brake operation.

When the total disc thickness is less than .965 for the

1"
thick disc or 1.215 for the 1-1/4" thick disc, it should

be replaced. Disc thicknesses less than this can permit

the shoes to come out of contact with the shoe abutments

and cause malfunction.

Because performance is not impaired by surface im-

perfection not exceeding .015 deep, refinishing of the

rubbing surface is not necessary.
Fig.
43—Dial Indicating Disc Runout

Since extremely accurate control of the finishing oper-

ation is necessary for proper performance and excess

metal removal can cause malfunction, refinishing of the

rubbing surface is not recommended.

Checking Procedure (Fig. 43)

Front

Tighten the adjusting nut of the wheel bearing until all

play has been removed. It should be just loose enough

to allow the wheel to turn. Clamp a dial indicator to the

caliper so that its button contacts the disc at a point about

1 inch from the outer edge. When the disc is turned, the

indicator reading should not exceed .002 inches. If runout

exceeds this amount the hub and disc assembly should

be replaced. Due to the close tolerances involved it is

not recommended that the front discs be machined or

serviced separately.

After checking the runout, readjust, the wheel bearings

as outlined in Section 3 of this manual.

Rear—Corvette Only

Check the rear wheel bearing end play, as outlined in

Section 4 of this manual. Then dial indicate the disc face.

If lateral runout of the disc exceeds the bearing end play

by .003 inches, the disc should be refaced (not to exceed

.040 inches) or replaced.

Removal

1.
Raise vehicle and remove wheel and tire assembly.

/ 2. Remove brake caliper as outlined in this section.

3.
Drill out the five rivets attaching the disc to the hub

or spindle.

4.
Remove brake disc from vehicle.

5. Complete the removal of the five rivets from the

hub or spindle.

Installation

1.
Install the disc to the hub or spindle aligning the lug

bolts with the holes in the disc.

CHEVROLET CHASSIS SERVICE MANUAL

BRAKES
5-31

POWER BRAKES

INDEX

General Description 5-31

Maintenance
and"
Adjustments 5-31

Inspection . ... 5_31

Lubrication 5-31

Bleeding Instructions . . . 5.31

Air Cleaner Service . . . , 5.31
Page

Component Replacement 5-31

Power Brake Cylinder ......* 5-31

Removal . . 5-31

Disassembly and Assembly See Overhaul Manual

Installation . . . . 5-31

GENERAL DESCRIPTION

The Power Brake Unit is a self-contained hydraulic

and vacuum unit, utilizing manifold vacuum and atmos-

phere pressure for its power.

This unit permits the use of a low brake pedal as well

as less pedal effort than is required with the conventional

(nonpower) hydraulic brake system. Only two external
line connections are necessary -
one
a vacuum connection

from manifold to check valve located on front shell; the

other, a hydraulic connection from the main cylinder

outlet directly into the hydraulic system. The unit is

mounted on the engine side of the fire wall and directly

connected to the brake pedal.

MAINTENANCE AND ADJUSTMENTS

INSPECTIONS

1.
Check vacuum line and vacuum line connections as

well as vacuum check valve in front shell of power

unit for possible vacuum loss.

2.
Inspect all hydraulic lines and connections at the

wheel cylinders and main cylinder for possible

hydraulic leaks.

3.
Check brake assemblies for scored drums, grease

or brake fluid on linings, worn or glazed linings,

and make necessary adjustments.

4.
Check brake fluid level in the hydraulic reser-

voirs.
The reservoirs should be filled to the levels

shown in Figure 8.

5. Check for loose mounting bolts at main cylinder and

at power section.

6. Check air cleaner filter in power piston extension

and replace filter if necessary.

7. Check brake pedal for binding and misalignment

between pedal
-and
push rod.

LUBRICATION

The power brake unit is lubricated at assembly and
needs no further lubrication other than maintaining

normal reservoir fluid level. The reservoir should be

filled as described in this section.

BLEEDING INSTRUCTIONS

The power system may be bled manually or with a

pressure bleeder as outlined in this section. Use only

GM
Supreme 11 Brake Fluid or equivalent. Do not use the

power assist while bleeding. The engine should not be

running and the vacuum reserve should be reduced to

zero by applying the brake several times before starting

the bleeding procedure.

AIR CLEANER SERVICE

Servicing of the air cleaner is recommended and the

element replaced when restriction becomes severe

enough to affect power brake response. At any other

time, if cleaning of the filter is felt necessary, it should

be shaken free of dirt or washed in soap and water and

thoroughly dried.

COMPONENT REPLACEMENT

POWER BRAKE CYLINDER

Removal

1.
Remove vacuum hose from vacuum check valve.

2.
Disconnect hydraulic lines at main cylinder.

Disconnect push rod at brake pedal assembly.

Remove nuts and lock washers securing power unit

to fire wall, and remove power unit from engine

compartment.
3.

4.

NOTE:
Chevy

to fire wall.
has a three stud attachment

Repair procedures for the power cylinder are outlined

in the Brake Section of the Overhaul Manual-for service
of the main cylinder refer to applicable portion of

"Standard Brakes" in this manual.

Installation

1.
Mount the power brake assembly in place and install

the attaching nuts and lock washers.

2.
Attach vacuum line to check valve.

3.
Secure hydraulic lines to main cylinder.

4.
Attach push rod to brake pedal assembly, and check

operation of stop light.

5. Bleed brakes as outlined in this section.

CAUTION: After replacing the unit on the vehi-

cle,
start the engine and allow vacuum to build

up before applying the brake.

CHEVROLET CHASSIS SERVICE

STEERING
9-32

arm on frame and install mounting bolts, washers

and nuts. No washer is used on Corvette.

Install relay rod to idler arm, ^making certain seal

is on stud. Install and tighten nut.

Install cotter pin.

Refer to torque specifications at rear of manual for'

correct torque values.

Chevy II (Fig. 62}

Removal

1.
Remove cotter pin, nut and washer securing idler

arm to relay rod.

2.
Remove relay rod from idler arm.

3.
If equipped with power steering disconnect power

cylinder shaft from idler arm bracket.

4.
Remove three idler bracket to frame bolts and nuts

and remove bracket and idler arm assembly.

5.
Remove cotter pin, nut, washer and bolt securing the

idler arm to the bracket.

6. Press out the idler arm bushing for replacement.

Installation

NOTE: Installation must be done with front

wheels straight ahead or the car will lead to one

side.

1.
Install idler arm bushing, if previously removed.

NOTE: Make certain the outer sleeve of the

bushing does not protrude above surface of idler

arm.

2.
Reverse removal procedure and torque all nuts ac-

cording to specifications.

PITMAN ARM

Removal

1.
Remove cotter pin from pitman arm ball stud and

remove nut.

2.
Remove relay rod from pitman arm by tapping on

side of rod or arm in which the stud mounts with a

hammer while using a heavy hammer or similar tool

as a backing. Pull down on relay rod to remove

from stud.

3.
Remove pitman arm nut from sector shaft and mark

relation of arm position to shaft.

4.
Remove pitman arm with Tool J-6632 as shown in

Figure 2.

Installation

1.
Install pitman arm on sector shaft, lining up the

• marks made upon removal.

2.
Install sector shaft nut.

3.
Position relay rod on to pitman arm. Install nut.

Continue to tighten arm enough to align castellation

with hole in stud and install cotter pin.
STEERING ARM

If, through collision or other damage, it becomes nec-

essary to remove and replace either steering arm, pro-

ceed as follows:

Removal

1.
Remove tie rod from steering arm as outlined in this

section.

2.
Remove front wheel, hub and brake drum as a unit

by removing hub cap and dust cap, cotter pin from

spindle nut and the spindle nut. Pull assembly to-

ward outside of vehicle. If removal is difficult, it

may be necessary to back off brake adjustment to

increase brake shoe-to-drum clearance; see Hy-

draulic Brake Adjustment, Section 5. On models

with disc brakes, remove caliper and disc.

3.
With wheel and drum assembly or caliper and disc

removed, steering arm retaining bolt heads are ac-

cessible and removal of steering arm from vehicle

may be accomplished by removing retaining nuts.

Installation

1.
Place steering arm in position on vehicle and install

retaining bolts*

2.
Install nuts. Use only the special locknut listed for

this use in the Chevrolet Parts Catalog.

3.
Pack wheel bearings using a high quality wheel

bearing lubricant. Install bearings and wheel-hub-

brake drum assembly removed previously. On disc

brake models, install disc and caliper.

4.
Install keyed washer and spindle nut. Proceed as out-

lined under t{ Front Wheel Bearing Adjustment" in

Section 3.

5.
Install tie rod ball stud in steering arm. Be sure that

the dust cover is in place on ball stud.

6. Install castellated nut on ball stud, tighten securely

and install cotter pin.

7.
Following directions given in Section 3 to check cor-

nering wheel relationship and toe-in; correct as

required.

STEERING DAMPER-CORVETTE

Removal

1.
Remove bolt from damper pivot bracket at relay rod.

2.
Remove nut from damper pivot at frame bracket and

withdraw damper assembly.

Damper is serviced as a unit. Replace damper if
3.

damaged or excessively worn.

Installation

1.
Place piston rod end into frame bracket and install

retainers, bushings, and nut.

2.
Insert cylinder end pivot into relay rod bracket and

install through bolt.

CHEVROLET CHASSIS SERVICE MANUAL

WHEELS AND TIRES 10-2

either case, tires will revolve with a side motion and

scrape the tread rubber off. If misalignment is severe,

the rubber will be scraped off of both tires (or all four

tires if front toe is not correct); if slight, only one will

be affected.

The scraping action against the face of the tire causes

a small feather edge of rubber to appear on
one .side
of

the tread and this feather edge is certain indication of

misalignment (fig. 1). The remedy is. readjusting toe-in

within specifications, or rechecking the entire front end

alignment if necessary.

Heei and Toe

This is a saw-toothed effect where one end of each

tread block is worn more than the other.

The end that wears is the one that first grips the road

when the brakes are applied.

Heel and toe wear is less noticeable onsrear tires than

on front tires, because the propelling action of the rear

wheels creates a force which tends to wear the opposite

end of the tread blocks. The two forces, propelling and

braking, make for more even wear of the rear tires,
whereas only the braking forces act on the front wheels,

and the saw-tooth effect is more noticeable.

A' certain amount of heel and toe wear is normal.

Excessive wear is usually due to high speed driving and

excessive use of brakes. The best remedy, in addition

UNDERINFLATION WEAR

Fig.
1 - Toe In or Toe Out Misalignment Wear
Fig.
2 - Over and Under Inflation Wear

CHEVROLET CHASSIS SERVICE MANUAL

WHEELS AND TIRES 10-3

Fig.
3 - Spof Wear

to cautioning the owner of his driving habits, is to inter-

change tires regularly.

Side

This may be caused by incorrect wheel camber, under-

inflation, high cambered roads or taking corners at too

high a rate of speed.

The first two causes are the most common. Camber

wear can be readily identified because it occurs only on

one side of the treads, whereas underinflation causes

wear on both sides (fig. 2).

There is, of course, no correction for high cambered

roads.
Cornering wear is discussed further on.

Center

This is caused primarily by overinflation pf the tire

(fig. 2). Invisible fabric damage can also be caused by

overinflation.

Uneven

Uneven or spotty wear (fig. 3) is due to such irregu-

larities as unequal caster or camber, bent front or rear

suspension parts, out-of-balance wheels, brake drums
Fig.
4 - Cornering Wear

out-of-round, brakes out-of-adjustment, or other me-

chanical conditions. The remedy in each case consists

of locating the mechanical defect and correcting it.

Cornering

Since the introduction of independent spring front and

rear wheels, improvements in spring suspension have

enabled drivers to negotiate curves at higher rates of

speed with the same feeling of security that they had

with the older cars at lower speeds. Consequently,

curves are being taken at higher speeds with the result

that a type of tire wear called "Cornering Wear" (fig. 4),

frequently appears.

When a car makes an extremely fast turn, the weight

is shifted from a normal loading on all four wheels to an

abnormal load on the tires on the outside of the curve

and a very light load on the inside tires due to centrifugal

force. This unequal loading may have two unfavorable

results.

First, the rear tire on the inside of the curve may be

relieved of so much load that it is no longer geared to

CHEVROLET CHASSIS SERVICE MANUAL

WHEELS AND TIRES 10-5

WHEELS

The wheel and tire assembly should be removed from

vehicles equipped with disc brakes to properly perform

balancing operations. This is necessary due to drag of

the spring loaded brake shoes on the disc.

Static Balancing (W/Tire)

Static Balance (still balance) is the equal distribution

of weight of the wheel and tire assembly about the axis

of rotation so that the assembly has no tendency to rotate

by
itself.
Static unbalance causes the pounding action of

the front wheels that is called "tramp".

To correct static unbalance (front and rear): The

quickest and best methods to correct static unbalance

are through the use of wheel balancers which are com-

mercially available. Refer to the Information and in-

structions included with these balaricers.

Dynamic Balancing (W/Tire)

Dynamic Balance (running balance) requires the wheel

to be not only in static balance, but balanced and running

smoothly while turning on an axis which runs through the

centerline of the wheel and tire perpendicular to the axis

of rotation.

The quickest and best methods of testing and correcting

dynamic unbalance are by the use of dynamic wheel

balancers which are commercially available. These bal-

ancers include all necessary information on where and

how the balancing weights should be placed. The follow-

ing information, however, will help in the correction of

dynamic balance.

NOTE:
Before attempting to balance the

wheels, check to be certain that no foreign

matter has been trapped in the wheel ventila-

tion slots or in the accessory wheel discs. This

is especially important if the vehicle has been
run in soft mud and then parked in freezing

weather.

When a wheel that is statically unbalanced is dynam-

ically in balance the dynamic balance can be retained

while correcting "the static balance by installing the cor-

rective weights so that half of the weight required is

placed on the inner edge of the rim and the other half

on the outer edge of the rim.

Dynamic unbalance can be corrected without destroying

static balance by installing weights so half of weight

required for dynamic balance is placed on the rim op-

posite the heavy point, while the other half is placed 180°

away and on the opposite side of the rim.

NOTE:
Vehicles with wire wheel covers should

have the wheels balanced with the wire wheel

covers installed on the wheels.

Run Out (W/OTire)

The wheels should not run out (wobble) more than

1/16" as measured on the side of the rim at the base

of the tire. Excessive run-out is the result of a bent

wheel, an improperly mounted wheel, worn knuckle bear-

ings or steering connections. These parts should be

checked for correct adjustment, proper alignment and

wear whenever excessive run-out is encountered.

The wheels should also run concentric with the steering

knuckle spindle within 1/16 inch as measured on the tire

bead seat of the rim with the tire removed.

Wheel run-out, eccentricity and balance are closely

associated with steering and front wheel alignment.

Further information on these subjects will be found under

"Suspension".

Cleaning Aluminum Wheels

Do not use wire brush or abrasive cleaners when

cleaning wheels. Use only cleaners that will not react

with aluminum.

SERVICE OPERATIONS

TIRES

Removal

Dismounting tubeless tires presents no problems if the

correct procedures are used and the following precau-

tions observed.

1.
Remove the valve cap and valve core. Let out all the

air.

2.
Press the inner side of the tire into the rim well.

Use bead loosening tool or if regular tire irons are

used, take particular care not to injure or tear the

sealing ribs on the bead.

CAUTION: Never use tire irons with sharp

edges or corners.

3.
Using tire irons on the opposite side, remove bead,

taking small "bites" around the rim.

4.
Turn the tire over, and use two tire irons, one be-

tween the rim flange and the bead to pry the rim

upward, the other iron to pry outward between the

bead seat and the bead.
Installation

Extreme care must be exercised to prevent injury to

the sealing bead and circumferential bead when forcing

tire over rim.

1.
Apply a light film of Ruglyde or other suitable rubber

lubricant to sealing bead of tire.

NOTE:
The use of excessive lubrication may

lead to rim slippage and subsequent breaking of

air seal.

2.
Carefully mount the outer bead in usual manner by

using tire irons, taking small "bites" around rim,

being careful not to injure the tire bead.

CAUTION: DO NOT use a hammer, as damage

to the bead will result.

3.
Install the inner bead in the same manner.

NOTE:
If a seal cannot be effected in the fore-

going manner with the rush of air it can be

, accomplished by applying to the circumference

of the tire a tire mounting band or heavy sash

cord and tightening with the use of a tire iron.

On tire mounting machines, bouncing the tire

assembly is not required. The tire should be

CHEVROLET CHASSIS SERVICE MANUAL