Manual Bleeding Procedure
BLEEDING BRAKE HYDRAULIC SYSTEM
CAUTION: Do not move the vehicle until a firm brake pedal is obtained. Air in the brake system can cause loss of brakes and could result in personal injury.
A bleeding operation is necessary to remove air from the hydraulic brake system whenever it is introduced into the hydraulic system.
It may be necessary to bleed the hydraulic system at all four brakes if air has been introduced through a low fluid level or by disconnecting brake pipes at the master cylinder. If a brake pipe is disconnected at one wheel, then that wheel cylinder/caliper only needs to be bled. If pipes are disconnected at any fitting located between master cylinder and brakes, then the brake system served by the disconnected pipe must be bled.
Manual Bleeding Procedure
Tool Required:
J 21472 Brake Bleeder Wrench
NOTICE: The use of rubber hoses or parts other than those specified for the Antilock Brake System may lead to functional problems requiring major overhaul. Replace all components included in repair kits used to service this system. Lubricate rubber parts with clean, fresh brake fluid to ease assembly. Do not use lubricated shop air on brake parts as damage to rubber components may result. If any hydraulic component is removed or brake line disconnected, it may be necessary to bleed all or part of the brake system. The torque values specified are for dry, unlubricated fasteners.
Remove the vacuum reserve by applying the brakes several times, with the engine off.
1. Fill the master cylinder reservoirs with brake fluid and keep at least half full of fluid during the bleeding operation.
2. If the master cylinder is known or suspected to have air in the bore, bleed it before any wheel cylinder or caliper in the following manner:
- Disconnect the front brake combination valve pipe fitting at the master cylinder.
- Allow brake fluid to fill the master cylinder bore until it begins to flow from the front brake combination valve pipe fitting port.
- Connect the front brake combination valve pipe to the master cylinder and tighten.
- Have a helper depress the brake pedal slowly one time and hold. Loosen the front brake combination valve pipe fitting at the master cylinder to purge air from the bore. Tighten the fitting and then have a helper release the brake pedal slowly. Wait 15 seconds. Repeat the sequence, including the 15 second wait, until all air is removed from the bore. Care must be taken to prevent brake fluid from contacting any painted surface.
Tighten
- Front brake combination valve pipe fitting at master cylinder to 32 Nm ( 24 lb ft. ).
- After all air has been removed at the front brake combination valve pipe fitting, repeat procedure outlined above to bleed the master cylinder at the rear brake combination valve fitting.
Tighten
- Rear brake combination valve pipe fitting at master cylinder to 32 Nm ( 24 lb. ft. ).
- If it is known that the calipers and wheel cylinders do not contain any air, it will not be necessary to bleed them.
3. Bleed individual wheel cylinders or calipers only after all air is removed from the master cylinder.
4. If it is necessary to bleed all of the wheel cylinders and calipers, follow this sequence:
- Right rear.
- Left rear.
- Right front.
- Left front.
5. Raise and suitably support vehicle.
- Place a proper size box end wrench or J 21472 over the bleeder valve.
- Attach a clear tube over bleeder valve and allow tube to hang submerged in a clear container partially filled with brake fluid.
- Have a helper depress the brake pedal slowly one time and hold. Loosen the bleeder valve to purge the air from the cylinder. Tighten bleeder valve and slowly release pedal, wait 15 seconds. Repeat the sequence, including the 15 second wait until all air is removed.
Tighten
- Caliper bleeder valve to 13 Nm ( 115 lb. in. ).
- Wheel cylinder bleeder valve to 7 Nm ( 62 lb. in. ).
- It may be necessary to repeat the sequence ten or more times to remove all the air.
- Rapid pumping of the brake pedal pushes the master cylinder secondary piston down the bore in a way that makes it difficult to bleed the rear side of the system.
- Lower vehicle.
- Fill master cylinder to proper level. Refer to "Filling Master Cylinder Reservoirs" in this section.
6. Check the brake pedal for "sponginess" and the red "BRAKE" warning lamp for indication of unbalanced pressure.
- Repeat entire bleeding procedure to correct either of these two conditions.