1990 Dodge Colt Brake Service (ONLINE REPAIR MANUALS)

• Grease or any other foreign material must be kept off the caliper, linings, surfaces of the disc and external surfaces of the hub, during service procedures. Handling the brake disc and caliper should be done in a way to avoid deformation of the disc and nicking or scratching brake linings.
• If inspection reveals that the rubber piston seals are worn or damaged, they should be replaced.
• During removal and installation of a wheel assembly, exercise care so as not to interfere with o...

DESCRIPTION

Bleeding the hydraulic brake system is necessary if air has entered the system. A few causes for this condition are low fluid level, a hydraulic fluid leak, a hydraulic line is opened, or replacement of a hydraulic system component. Symptoms can be noted by an improper or loss of brake operation, and/or a low or spongy brake pedal.

Flushing the hydraulic brake system is necessary if contaminates are found in the hydraulic system. A few causes for hydraulic system contamination are moisture, age of hydraulic system parts and fluid, or improper fluid...

These units are of the vacuum suspended type. Some units are of the single diaphragm type,Fig. , while others are of the tandem diaphragm type,Fig. . Both single piston and double piston or split system type master cylinders are used.

The vacuum suspended diaphragm type units utilize engine manifold vacuum and atmospheric pressure for its power. It consists of three basic elements combined into a single power unit. The three basic elements of the single diaphragm type are:

• A vacuum power section which includes a front and rear shell, a power diaphragm, a return spring...

Should it become necessary to remove the caliper for installation of new parts, clean all parts in denatured alcohol, wipe dry using lint-free cloths. Using an air hose, blow out drilled passages and bores. Check dust boots for punctures or tears. Generally, 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 bore is not...

In order to properly service and repair available brake systems, a thorough understanding of the power assist systems is necessary. The vacuum assist diaphragm assembly multiplies the force exerted on the master cylinder piston in order to increase the hydraulic pressure delivered to the wheel cylinders or calipers while decreasing the effort necessary to obtain acceptable stopping performance.

Vacuum assist units get their energy by opposing engine vacuum to atmospheric pressure. A piston, cylinder and flexible diaphragm utilize this energy to provide brake assistance. The diaph...

Maintenance of disc brakes is extremely critical for proper brake operation due to close tolerances required in machining the brake disc. In addition, the disc rubbing surface must be non-directional and maintained at a micro inch finish to control erratic performance, promote long lining life, and equal lining wear of both left and right brakes.

Refinishing of the rubbing surfaces should not be attempted unless precision equipment, capable of measuring in micro inches (millionths of an inch) is available.

LATERAL RUNOUT CHECK

Refer to "Rotor Specifications" for runout specificati...