1991 Chevrolet Corvette Brake Service (ONLINE REPAIR MANUALS)

BLEEDING BRAKES

Manual Bleeding

Pressure bleeding is recommended for all hydraulic systems. However, if a pressure bleeder is unavailable, use the following procedure.Brake fluid damages painted surfaces. Immediately clean any spilled fluid.

• Remove vacuum reserve by pumping brakes several times with engine off.
• Fill master cylinder reservoir with clean brake fluid. Check fluid level often during bleeding procedure; do not let reservoir fall below half full.
• If necessary, bleed master cylinder as follows:
• Disconnect master cylinder forward brake line connection until fluid flows from re...

Should it become necessary to remove the caliper for installation of new parts, clean all parts in alcohol, wipe dry using lint free cloths, using an air hose to blow out drilled passages and bores. Check dust boots for punctures or tears. If punctures or tears are evident, new boots should be installed upon reassembly.

Inspect piston bores for scoring or pitting. Bores that show light scratches or corrosion can usually be cleaned with crocus cloth. However, bores that have deep scratches or scoring may be honed, provided the diameter of the...

COMPOSITE TYPE

Refer toFigs. and when performing the following procedures.

EXCEPT CORVETTE

Disassembly

• Remove master cylinder from vehicle as follows:
• Disconnect and plug hydraulic lines.
• Remove two master cylinder attaching nuts, then the master cylinder.
• Remove reservoir cover and diaphragm. Discard old brake fluid in reservoir.
• Inspect cover and diaphragm. Replace if cut, cracked or deformed.
• Remove fluid level switch, if equipped.
• On models with compact master cylinder, remove proportioner valve assembly,Fig. .
• Depress primary piston and remove lock ring.
• Plug primary fluid ou...

Two basic types of power assist mechanisms are used: vacuum assist diaphragm assemblies, which use engine vacuum or, in some cases vacuum pressure developed by an external vacuum pump. The second type is a hydraulic pressure assist mechanism, which use pressure developed by an external pump (usually the power steering pump). Both systems act to increase the force exerted on the master cylinder piston by the operator. This in turn increases the hydraulic pressure delivered to the wheel cylinders, while decreasing driver effort necessary to obtain acceptable stopping performance.

V...

When ignition switch is turned to On position, amber ANTI-LOCK warning lamp in the instrument panel illuminates. When engine is started, it goes out. If ABS warning light does not go out or comes on permanently while driving, it indicates a fault in ABS system.

When starting vehicle, the control module performs a functional check of electrical circuitry. The test cycle checks components of the monitoring circuit as well as the logic section. Test sample signals are sent to the control module, which checks whether or not the correct output signals are available.

Since the ABS system may ...

• Raise and support vehicle.
• Remove wheel, drum and brake shoes.
• Disconnect hydraulic line at wheel cylinder.Do not pull metal line away from cylinder, as this may kink or bend line. Line will separate from cylinder when cylinder is moved away from brake backing plate.
• Remove wheel cylinder-to-brake plate attaching screws, then the wheel cylinder.
• Remove boots, pistons, springs and cups from cylinder,Fig. .
• Clean all parts with brake fluid.
• Inspect cylinder bore. A scored bore may be honed as long as the diameter is not increased by m...