Fig. 5 Brake Drum Adjustment With Tool C-3784

support plate (Fig. 4) to provide access to the adjuster star wheel. Then, to eliminate the possibility of maximum adjustment, where the adjuster does not operate because the closest possible adjustment has been reached. Back the star wheel off approximately 30 notches. It will be necessary to hold the adjuster lever away from the star wheel to permit this adjustment.

Spin the wheel and brake drum in the reverse direction, and with a greater than normal force apply the brakes suddenly. This sudden application of force will cause the secondary brake shoe to leave the anchor. The wrap up effect will move the secondary shoe, and the cable will pull the adjuster lever up. Upon application of the brake pedal, the lever should move upward, turning the star wheel. Thus, a definite rotation of the adjuster star wheel can be observed if the automatic adjuster is working properly. If one or more adjusters do not function properly, the respective drum must be removed for adjuster servicing.

BLEEDING BRAKE SYSTEM

CAUTION: For bleeding of the Anti-Lock brake hydraulic system. See the Anti-Lock Brake system service procedures in this group which refers to the particular Anti-Lock brake system being serviced.

PRESSURE BLEEDING

Before removing the master cylinder cover, wipe it clean to prevent dirt and other foreign matter from dropping into the master cylinder.

CAUTION: Use bleeder tank Special Tool C-3496-B with adapter Special Tool C-4578 to pressurize the system for bleeding.

Follow pressure bleeder manufacturer's instructions, for use of pressure bleeding equipment.

When bleeding the brake system. Some air may be trapped in the brake lines or valves far upstream. As much as ten feet from the bleeder screw (Fig. 6). Therefore, it is essential to have a fast flow of a large volume of brake fluid when bleeding the brakes to ensure all the air gets out.

Fig. 6 Trapped Air in Brake Line

To bleed the brake system. Attach a clear plastic hose to the bleeder screw at one wheel and feed the hose into a clear jar containing fresh brake fluid (Fig. 7).

Fig. 7 Proper Method for Purging Air From Brake System (Typical)

Next, open the bleeder screw at least one full turn or more to obtain an adequate flow of brake fluid (Fig. 8).

CAUTION: Just cracking the bleeder screw often restricts fluid flow, and a slow, weak fluid discharge will NOT get all the air out.

After 4 to 8 ounces of fluid has been bled through the brake system. And an air-free flow is maintained in the clear plastic hose and jar, this will indicate a good bleed.