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Hydraulic Brake System Bleeding Manual

Bleeding the brake is necessary if air has entered the hydraulic brake system.

Bleed the system at all four wheels if a low fluid level has allowed air to enter the system or the brake pipes have been disconnected at the master cylinder. If a pipe is disconnected at one wheel, bleed only that wheel.

Bleed the master cylinder before you install the master cylinder into the vehicle. Bleeding the cylinder reduces the time required to bleed the hydraulic system when you remove the master cylinder.

Use the Hydraulic Brake System Bleeding procedure if the Electric Hydraulic Control Unit (EHCU) has not been replaced. If the EHCU has been replaced, refer to the ABS Bleeding Procedure in Antilock Brakes for the proper bleeding procedures.

    Notice: Brake fluid will damage electrical connections and painted surfaces. Use shop cloths, suitable containers, and fender covers to prevent brake fluid from contacting these areas. Always re-seal and wipe off brake fluid containers to prevent spills.

  1. Fill the master cylinder reservoirs with DOT 3 motor vehicle brake fluid. Maintain the fluid level during the bleeding procedure.
  2. Perform the following procedure if you suspect the master cylinder has air in the bore:
    3. 2.1. Bleed the master cylinder before bleeding any wheel cylinder brake caliper.
    2.2. Disconnect the forward brake pipe connection at the master cylinder.
    2.3. Allow the brake fluid to flow from the connector port.
    2.4. Connect the brake pipe.

    Do not tighten the brake pipe.

    2.5. Apply the brake pedal slowly.

    Allow the air to bleed from the loose fitting.

    2.6. Tighten the fitting before releasing the pedal.
    2.7. Wait 15 seconds.
    2.8. Repeat this sequence, including the 15  second wait, until the air is plunged from the bore.
    2.9. Repeat the procedure for the rear pipe after all of the air is removed from the forward connection.
  3. Bleed the brake system in the following sequence:
    4. 3.1. The right rear
    3.2. The left rear
    3.3. The right front
    3.4. The left front

    Object Number: 220731 Size: SH
  4. Attach a hose to the caliper bleeder valve. Immerse the opposite end of the hose into a container that is partially filled with clean brake fluid.
  5. Slowly apply the brake pedal one time and hold the brake pedal.
  6. Loosen the bleeder valve in order to purge the air from the caliper.
  7. Tighten the bleeder valve and slowly release the pedal.
  8. Wait 15 seconds.
  9. Repeat the sequence, including the 15 second wait, until all of the air is purged from the caliper.
  10. Continue steps 4 through 9 at each wheel until the brake system has been bled.
  11. Inspect the brake pedal for sponginess. Repeat the bleeding procedure if the brake is spongy.

Hydraulic Brake System Bleeding Pressure


Object Number: 208940 Size: SH

Bleeding is necessary if air has entered the hydraulic system.

Bleed the system at all four wheels if a low fluid level has allowed air to enter the system or the brake pipes has been disconnected at the master cylinder. If a pipe is disconnected at one wheel, then only bleed that wheel.

Bleed the master cylinder before you install the master cylinder into the vehicle.Bleeding the cylinder reduces the time required to bleed the hydraulic system when you remove the master cylinder.

Use the Hydraulic Brake System Bleeding procedure if the Electric Hydraulic Control Unit (EHCU) has not been replaced. If the EHCU has been replaced, refer to the ABS Bleed Procedure in Antilock Brakes for the proper bleeding procedures.

Tools Required

    • J 29532 Power Brake Bleeder
    • J 33855 Pressure Bleeder Adapter

Notice: Brake fluid will damage electrical connections and painted surfaces. Use shop cloths, suitable containers, and fender covers to prevent brake fluid from contacting these areas. Always re-seal and wipe off brake fluid containers to prevent spills.

Use a diaphragm type pressure bleeder. The bleeder must have a rubber diaphragm between the air supply and the brake fluid in order to prevent the following from contaminating the hydraulic system:

    • Air
    • Moisture
    • Oil
    • Other contaminants
  1. Fill the pressure tank at least 2/3 full with the brake fluid. Bleed the bleeder each time the fluid is added.
  2. Charge the bleeder to 140 to 170 kPa (20 to 25 psi).
  3. Install the J 33855 Pressure Bleeder Adapter on the master cylinder.
  4. Connect the hose from the bleeder to the adapter.
  5. Open the tank valve.
  6. Bleed the brake system in the following sequence:
    7. • The right rear
    • The left rear
    • The right front
    • The left front

    Object Number: 220731 Size: SH
  7. Attach the hose to the bleeder valve. Immerse the opposite end of the hose into a container that is partially filled with clean brake fluid.
  8. Open the bleeder valve at lease 3/4 of a turn. Allow the fluid to flow until no air is found in the fluid.
  9. Close the bleeder valve.
  10. Repeat steps 7 through 9 at each wheel.
  11. Inspect the brake pedal for sponginess. Repeat the entire bleeding procedure if the brake pedal is spongy.
  12. Disconnect the line from the bleeder adapter.
  13. Remove the bleeder adapter.
  14. Fill the master cylinder to the proper fluid level. Refer to Master Cylinder Reservoir Filling .