Chevrolet 1963 Corvette, Руководство по ремонту и настройке

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BRAKES 269
Pressure Bleeding
1. Clean the top of the master cylinder,
remove the cover, and attach the pressure
bleeding adapter.
2. Check die pressure bleeder reservoir for
correct pressure and fluid level, then open
the release valve.
3. Fasten a bleeder hose to the wheel cyl
inder bleeder nipple and submerge the free
end of the hose in a transparent receptacle.
The receptacle should contain enough brake
fluid to cover the open end of the hose.
4. Open the wheel cylinder bleeder nip
ple and allow the fluid to flow until all bub
bles disappear and an uncontaminated flow
exists.
5. Close the nipple, remove the bleeder
hose and repeat the procedure on the other
wheel cylinders according to the bleeding se
quence.
Manual Bleeding
An alternative to the pressure method of
bleeding requires two people to perform: one
to depress the brake pedal and the other to
open the bleeder nipples.
1. Observe the cleaning operation of the
pressure method, then remove the cover and
fill the reservoir.
2. Attach a bleeder hose and clear con
tainer as before.
3. Have the assistant depress the brake
pedal to the floor, and then pause until fluid
flow ceases and the bleeder nipple is closed.
4. Allow the pedal to return and repeat the
procedure until a steady, bubble-free flow is
seen.
5. Secure the nipple and move to the other
wheels in the correct sequence.
6. Periodically check the master cylinder
for an adequate supply of fluid. If the reser
voir runs dry, air will enter the system and
bleeding will have to be done again.
DRUM BRAKES (FRONT OR
REAR)
Brake Drums
REMOVAL AND INSTALLATION
1. Jack the car so wheels are off the ground.
2. Remove the wheel or wheels where
brake drums are to be removed.
3. Pull the brake drum off—it may be nec-
essary to gently tap the rear edges of the drum
to start it off the studs.
4. If extreme resistance to removal is en
countered, it will be necessary to retract the
adjusting screw. Knock out the access hole in
the brake drum and turn the adjuster to re
tract the linings.
5. Install brake drums after adjusting the
linings.
6. Install the drums in the same position
on the hub or axle shaft as removed.
INSPECTION
When a drum is removed, it should be in-
spected for cracks, scores, or other imperfec-
tions. These must be corrected before the
drum is replaced.
CAUTION: If the drum is found to be
cracked, replace it. Do not attempt to ser-
vice a cracked drum.
Minor drum score marks can be removed
with fine emery cloth. Heavy score marks
must be removed by "turning the drum." This
is removing the metal from the entire inner
surface of the drum in order to level the sur-
face. Automotive machine shops and some
large parts stores are equipped to perform this
operation.
If the drum is not scored, it should be pol-
ished with fine emery cloth before replace-
ment. If the drum is resurfaced, it should not
be enlarged past 0.060 in. of the original di-
ameter.
It is advisable, while the drums are off, to
check them for out-of-round. An inside mi-
crometer is necessary for an exact measure-
ment, therefore unless this tool is available,
the drums should be taken to a machine shop
to be checked. Any drum which is more than
0.006 in. out-of-round will result in an inac-
curate brake adjustment and other problems,
and should be refinished or replaced. NOTE:
If the micrometer is available, make all
measurements at right angles to each other
and at the open and closed edges of the
drum machined surface. Check the drum
with a micrometer in the following manner:
1. Position the drum on a level surface.
2. Insert the micrometer with its adapter
bars if necessary.
3. Obtain a reading on the micrometer at
the point of maximum contact. Record this.
4. Rotate the micrometer 45° and take a
similar reading. The two readings must not
vary more than 0.006 in.