Brake Bleeding: Service and Repair

CAUTION: Do not move the vehicle until a firm brake pedal is obtained. Air In the brake system can cause the loss of brakes with possible personal injury.

A bleeding operation is necessary in order to remove air from the hydraulic brake system whenever air is introduced into the brake system.
Bleed the hydraulic system at all four brakes if air has been introduced into the system through low fluid level or by disconnecting the brake pipes at the master cylinder. If a brake pipe is disconnected at one wheel, bleed only that wheel cylinder/caliper. If the pipes are disconnected at any fitting located between the master cylinder and brakes, bleed the brake system served by the disconnected pipe.
Observe the following steps in order to reduce the time required to bleed the hydraulic system:
^ Ensure that the master cylinder reservoir is filled with brake fluid.
^ Expel as much air as possible before installing the master cylinder on the vehicle.

MANUAL BLEEDING

Tools Required
^ J 21472 Brake Bleeder Wrench

Apply the brakes several times with the ignition OFF. This will deplete the vacuum reserve. Use extreme care in order to prevent brake fluid from contacting painted surfaces.
1. Fill the master cylinder reservoir with the specified brake fluid in Maintenance and Lubrication in General Information.
^ Maintain the fluid level in the reservoir during the bleeding operation.
^ Use an assistant in the vehicle in order to press the brake pedal during the manual bleeding process.
2. If the master cylinder is known or suspected to have air in the bore, bleed the master cylinder before the wheel cylinder or the calipers are bled. Complete the following steps:





3. Disconnect the forward brake pipe connections) (1) at the master cylinder.
4. Fill the master cylinder with brake fluid until fluid begins to flow from the forward pipe connector port.
5. Connect the forward brake pipe to the master cylinder. Tighten the pipe.
6. Slowly depress the brake pedal and hold the pedal.
7. Loosen the forward brake pipe connection at the master cylinder in order to purge air from the cylinder.
8. Tighten the connection.
9. Slowly release the brake pedal.
10. Wait 15 seconds.
11. Repeat the previous eight steps until all air is removed from the bore.
Use extreme care in order to prevent brake fluid from contacting painted surfaces.
12. Bleed the master cylinder at the rear (cowl end) connections after all the air has been removed at the forward connections. Slowly depress the brake pedal and hold the pedal.
13. Check for a firm pedal feel and proper brake pedal travel. If the wheel cylinders and calipers do not contain air, bleeding is not necessary, but recommended in order to remove any moisture or debris.
14. After all air is removed from the master cylinder, bleed the wheel cylinders in the following order, if necessary:
14.1. Right rear
14.2. Left rear
14.3. Right front
14.4. Left front
15. Raise the vehicle. Support the vehicle. Refer to Vehicle Lifting and Jacking.





16. Place a proper size box end wrench (1) (or special tool) over the caliper/cylinder bleeder valve.
17. Attach a transparent tube (2) over the bleeder screw.
Submerge the other end in a transparent container partially filled with clean brake fluid.
18. Slowly depress the brake pedal and hold the pedal.
19. Loosen the bleeder screw in order to purge the air from the cylinder/caliper.

NOTICE: Always use the correct fastener in the proper location. When you replace a fastener, use ONLY the exact part number for that application. The manufacturer will call out those fasteners that require a replacement after removal. The manufacturer will also call out the fasteners that require thread lockers or thread sealant. UNLESS OTHERWISE SPECIFIED, do not use supplemental coatings (paints, greases, or other corrosion inhibitors) on threaded fasteners or fastener joint interfaces. Generally, such coatings adversely affect the fastener torque and joint clamping force, and may damage the fastener. When you install fasteners, use the correct tightening sequence and specifications. Following these instructions can help you avoid damage to parts and systems.

20. Tighten the bleeder screw.
^ Tighten the rear bleeder screws to 7 Nm (62 inch lbs.).
^ Tighten the front bleeder screws to 13 Nm (115 inch lbs.).

21. Slowly release the pedal.
22. Wait 15 seconds.
23. Repeat the previous five steps until all air is removed from the caliper.
Do not pump the brake pedal rapidly. Pumping the pedal pushes the master cylinder secondary piston down the bore which causes difficult bleeding.
24. Lower the vehicle.





25. Fill the master cylinder to the proper level.
26. Check the brake pedal for sponginess or excessive travel.
Repeat the entire manual bleeding procedure in order to correct either of the two conditions.





PRESSURE BLEEDING

Tools Required
^ J 29532 Diaphragm Type Brake Bleeder
^ J 35589 pressure Bleeder Adapter Cap
^ J 21472 Brake Bleeder Wrench

NOTICE: Pressure bleeding equipment must be of the diaphragm type. It must have a rubber diaphragm between the air supply and the brake fluid to prevent air, moisture, oil and other contaminants from entering the hydraulic system.

1. Install the J 35589 to the master cylinder
2. Charge the J 29532 to 140-172 kPa (20-25 psi).
3. Connect the line to the J 35589.
4. Open the line valve.
5. Raise the vehicle. Support the vehicle. Refer to Vehicle Lifting and Jacking.
6. Bleed the wheel cylinders/calipers in the following order, if necessary:
6.1. Right rear
6.2. Left rear
6.3. Right front
6.4. Left front
7. Place the J 21472 over the caliper/cylinder bleeder valve.
8. Attach a transparent tube over the bleeder screw.
Submerge the opposite hose end in a transparent container partially filled with clean brake fluid.
9. Open the bleeder screw at least 3/4 of a turn.
Allow the fluid to flow until no air is visible in the fluid.
10. Close the bleeder screw.
^ Tighten the rear bleeder screws to 7 Nm (6.2 inch lbs.).
^ Tighten the front bleeder screws to 13 Nm ( 115 inch lbs.).

11. Repeat the previous four steps until all of the calipers/cylinders have been bled.
12. Lower the vehicle.
13. Inspect the brake pedal for sponginess. Repeat this entire pressure bleeding procedure in order to correct this conditions.
14. Remove the J 35589 and the J 29532.





15. Fill the master cylinder to the proper level.