Base Brake Bleeding
BASE BRAKE BLEEDING
CAUTION: Before removing the master cylinder cover, wipe it clean to prevent dirt and other foreign matter from dropping into the master cylinder.
CAUTION: Use only Mopar(R) brake fluid or an equivalent from a fresh, tightly sealed container. Brake fluid must conform to DOT 3 specifications.
NOTE: For bleeding the antilock brake hydraulic system
NOTE: Do not pump the brake pedal at any time while having a bleeder screw open during the bleeding process. This will only increase the amount of air in the system and make additional bleeding necessary.
NOTE: Do not allow the master cylinder reservoir to run out of brake fluid while bleeding the system. An empty reservoir will allow additional air into the brake system. Check the fluid level frequently and add fluid as needed.
The following wheel circuit sequence for bleeding the brake hydraulic system should be used to ensure adequate removal of all trapped air from the brake hydraulic system.
- Right rear wheel
- Left rear wheel
- Right front wheel
- Left front wheel
NOTE: Pressure bleeding is highly recommended to bleed this brake system to ensure all air is removed from system. Manual bleeding may also be used, but additional time is needed to remove all air from system.
The base brake system can be bled using the pressure method or the manual method. Both methods are presented in this text.
PRESSURE BLEEDING METHOD
NOTE: Follow pressure bleeder manufacturer's instructions for use of pressure bleeding equipment.
1. Remove filler cap from the top of fluid reservoir (2) on master cylinder.
2. Install Adapter (1), Special Tool 6921, in the caps place on the reservoir (2).
3. Attach Bleeder Tank, Special Tool C-3496-B, or equivalent, to Adapter 6921 (1). Pressurize the system following the pressure bleeder manufacturer's instructions.
NOTE: To ensure all air is bled from the ICU or junction block in a timely manner, it is recommended to raise the rear of the vehicle approximately 5� higher than the front or approximately 10-12 inches as measured at the rear bumper (1).
4. Raise and support vehicle placing rear of vehicle approximately 5� higher than the front or if measured at the rear bumper (1), approximately 10-12 inches above level. It will be necessary to add extra support stands under vehicle to support this angle.
5. If installed, remove rubber dust caps from all four bleeder screws on calipers.
6. Starting at the first wheel circuit as listed earlier, attach a clear hose (1) to the bleeder screw at that wheels brake caliper and feed the other end of hose into a clear jar (2) containing enough fresh brake fluid to submerge the end of the hose.
CAUTION: Open the bleeder screw at least one full turn when instructed. Some air may be trapped in the brake lines or valves far upstream, as far as ten feet or more from the bleeder screw. If the bleeder screw is not opened sufficiently, fluid flow is restricted causing a slow, weak fluid discharge. This will NOT get all the air out. Therefore, it is essential to open the bleeder screw at least one full turn to allow a fast, large volume discharge of brake fluid.
7. Open bleeder screw at least one full turn or more to obtain an adequate flow of brake fluid.
8. After 4 to 8 ounces of brake fluid has been bled through the brake hydraulic circuit, and an air-free flow (no bubbles) is maintained in the clear plastic hose (1) and jar (2), close the bleeder screw.
9. Bleed the remaining wheel circuits in the same manner until all air is removed from the brake hydraulic system.
10. Check brake pedal travel. If pedal travel is excessive or has not improved, some air may still be trapped in the hydraulic system. Rebleed the brake system as necessary.
11. If equipped with antilock brakes, the hydraulic control unit may need to be bled, then rebleed base brakes.
12. Reinstall all 4 bleeder screw dust caps.
13. Test drive vehicle to ensure brakes are operating properly and pedal feel is correct.
MANUAL BLEEDING METHOD
NOTE: To bleed the base brake system manually, an assistants help is required.
NOTE: To ensure all air is bled from the ICU or junction block in a timely manner, it is recommended to raise the rear of the vehicle approximately 5� higher than the front or approximately 10-12 inches as measured at the rear bumper (1).
1. Raise and support vehicle placing rear of vehicle approximately 5� higher than the front or if measured at the rear bumper (1), approximately 10-12 inches above level. It will be necessary to add extra support stands under vehicle to support this angle.
2. Remove rubber duct caps from all 4 bleeder screws.
3. Attach a clear hose (1) to the bleeder screw at one wheel and feed the other end of the hose into a clear jar (2) containing fresh brake fluid.
4. Have an assistant pump the brake pedal three or four times and hold it down before the bleeder screw is opened.
CAUTION: Open the bleeder screw at least one full turn when instructed. Some air may be trapped in the brake lines or valves far upstream, as far as ten feet or more from the bleeder screw. If the bleeder screw is not opened sufficiently, fluid flow is restricted causing a slow, weak fluid discharge. This will NOT get all the air out. Therefore, it is essential to open the bleeder screw at least one full turn to allow a fast, large volume discharge of brake fluid.
5. While the pedal is being held down, open the bleeder screw at least 1 full turn. When the bleeder screw opens the brake pedal will drop all the way to the floor. Continue to hold the pedal all the way down.
6. Once the brake pedal has dropped, close the bleeder screw. The pedal can then be released.
7. Repeat steps One through Five until all trapped air is removed from that wheel circuit (usually four or five times). This should pass a sufficient amount of fluid to expel all the trapped air from the brakes hydraulic system. Be sure to monitor brake fluid level in master cylinder fluid reservoir making sure it stays at a proper level. This will ensure air does not reenter brake hydraulic system through master cylinder.
NOTE: Monitor the brake fluid level in the fluid reservoir periodically to make sure it does not go too low. This will ensure that air does not reenter the brake hydraulic system.
8. Bleed the remaining wheel circuits in the same manner until all air is removed from the brake hydraulic system.
9. Check brake pedal travel. If pedal travel is excessive or has not improved, some air may still be trapped in the hydraulic system. Rebleed the brake system as necessary.
10. If equipped with antilock brakes, the hydraulic control unit may need to be bled, then rebleed base brakes.
11. Reinstall all 4 bleeder screw dust caps.
12. Test drive vehicle to ensure brakes are operating properly and pedal feel is correct.