Base Brake System
STANDARD PROCEDURE - BASE BRAKE BLEEDINGNOTE: There are two methods of brake bleeding. Refer to Manual Bleeding Method or Pressure Bleeding Method.
MANUAL BLEEDING METHOD
NOTE:
- Correct manual bleeding of the brakes hydraulic system will require the aid of a helper.
- The following wheel sequence should be used when bleeding the brake hydraulic system. The use of this wheel sequence will ensure adequate removal of all trapped air from the brake hydraulic system.
- Left Rear Wheel
- Right Front Wheel
- Right Rear Wheel
- Left Front Wheel
CAUTION: Slightly opening the bleeder screw often restricts the flow of brake fluid. A slow weak flow of brake fluid from the bleeder screw will NOT get all the air out.
1. Pump the brake pedal three or four times and hold it down before the bleeder screw is opened.
2. Push the brake pedal toward the floor and hold it down. Then open the left rear bleeder screw at least 1 full turn. When the bleeder screw opens the brake pedal will drop all the way to the floor.
3. Release the brake pedal only after the bleeder screw is closed.
4. Repeat steps 1 through 3, four or five times, at each bleeder screw in the required sequence. This should pass a sufficient amount of fluid to expel all the trapped air from the brake system. Be sure to monitor the fluid level in the master cylinder, so it stays at a proper level so air will not enter the brake system through the master cylinder.
5. Test drive the vehicle to be sure the brakes are operating correctly and a solid brake pedal has been obtained.
PRESSURE BLEEDING METHOD
CAUTION:
- Before removing the cap from the master cylinder fluid reservoir, thoroughly clean the cap and fluid reservoir to prevent dirt from dropping into the master cylinder fluid reservoir.
- Use bleeder tank Special Tool C-3496-B with adapter Special Tool 6921 to pressurize the hydraulic system for bleeding.
Follow the 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 as far upstream as ten feet from the bleeder screw. 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 goes out.
1. Remove the cap from the master cylinder fluid reservoir.
2. Install the Adapter Master Cylinder Pressure Bleed Cap, Special Tool 6921, on the fluid reservoir of the master cylinder. Attach the fluid hose from the pressure bleeder to the fitting on Special Tool 6921.
3. Attach a clear plastic hose to the bleeder screw at one wheel and feed the hose into a clear jar containing fresh brake fluid.
NOTE: The following wheel sequence should be used when bleeding the brake hydraulic system. The use of this wheel sequence will ensure adequate removal of all trapped air from the brake hydraulic system.
- Left Rear Wheel
- Right Front Wheel
- Right Rear Wheel
- Left Front Wheel
CAUTION: Slightly opening the bleeder screw often restricts the flow of brake fluid. A slow weak flow of brake fluid from the bleeder screw will NOT get all the air out.
4. Open the left rear brake caliper bleeder screw at least one full turn or more to obtain an adequate flow of brake fluid.
5. After 4 to 8 ounces of brake fluid has been bled through the left rear brake caliper and hydraulic system, with an air-free flow of brake fluid maintained, a good bleed of the hydraulic system to the left rear wheel has been obtained.
6. Repeat the procedure at all the other remaining bleeder screws. Then check the pedal for travel. If pedal travel is excessive or has not been improved, enough fluid has not passed through the system to expel all the trapped air. Be sure to monitor the fluid level in the pressure bleeder, so it stays at a proper level so air will not enter the brake system through the master cylinder.
7. Test drive the vehicle to be sure the brakes are operating correctly and that a solid brake pedal has been obtained.