Hydraulic Brake System Bleeding Manual

Warning: Refer to Brake Fluid Irritant Warning in the Preface section.

Caution: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. The use of any type of fluid other than the recommended type of brake fluid, may cause contamination which could result in damage to the internal rubber seals and/or rubber linings of hydraulic brake system components.

Caution: Refer to Brake Fluid Effects on Paint and Electrical Components Caution in the Preface section.

1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills.
2. With the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort increases significantly, in order to deplete the brake booster power reserve.

Note: If you have performed a brake master cylinder bench bleeding, disconnected the brake pipes from the master cylinder, replaced the ABS pressure modulator valve, or disconnected the jumper lines from the master cylinder to the ABS pressure valve, you MUST use the pressure bleeding procedure to remove all the air from the system. Refer to Hydraulic Brake System Bleeding.

3. Fill the brake master cylinder reservoir with Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. Ensure that the brake master cylinder reservoir remains at least half-full during this bleeding procedure. Add fluid as needed to maintain the proper level.

Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm.

4. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
5. Install a transparent hose over the end of the bleeder valve.
6. Submerge the open end of the transparent hose into a transparent container partially filled with Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
7. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the pedal.
8. Loosen the bleeder valve to purge air from the wheel hydraulic circuit.
9. Tighten the bleeder valve, then have the assistant slowly release the brake pedal.
10. Wait 15 seconds, then repeat steps 7-9 until all air is purged from the same wheel hydraulic circuit.
11. With the right rear wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the right rear hydraulic circuit, install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
12. Install a transparent hose over the end of the bleeder valve, then repeat steps 6-10.
13. With the left front wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the left front hydraulic circuit, install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
14. Install a transparent hose over the end of the bleeder valve, then repeat steps 6-10.
15. With the left rear wheel hydraulic circuit bleeder valve tightened securely, after all air has been purged from the left rear hydraulic circuit, install a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve.
16. Install a transparent hose over the end of the bleeder valve, then repeat steps 6-10.
17. After completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4 wheel hydraulic circuit bleeder valves are properly tightened.
18. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
19. Slowly depress and release the brake pedal. Observe the feel of the brake pedal.

Note: If it is determined that air was induced into the system upstream of the ABS modulator prior to servicing, the Antilock Brake System Automated Bleed Procedure must be performed.

20. If the brake pedal feels spongy, repeat the bleeding procedure again. If the brake pedal still feels spongy after repeating the bleeding procedure, perform the following steps:

20.1.

Inspect the brake system for external leaks. Refer to Brake System External Leak Inspection.

20.2.

Pressure bleed the hydraulic brake system in order to purge any air that may still be trapped in the system.

21. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp remains illuminated.

Note: DO NOT allow the vehicle to be driven until it is diagnosed and repaired.

22. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes.

Hydraulic Brake System Bleeding Pressure

Special Tools

Warning: Refer to Brake Fluid Irritant Warning in the Preface section.

Caution: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. The use of any type of fluid other than the recommended type of brake fluid, may cause contamination which could result in damage to the internal rubber seals and/or rubber linings of hydraulic brake system components.

Caution: Refer to Brake Fluid Effects on Paint and Electrical Components Caution in the Preface section.

1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills.
2. With the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort increases significantly, in order to deplete the brake booster power reserve.
3. If you have performed a brake master cylinder bench bleeding on this vehicle, replaced the ABS pressure modulator valve, or disconnected the brake lines between master cylinder and ABS on this vehicle, you must perform the following steps:

3.1.	Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary, add Delco Supreme 11® GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.

If removal of the reservoir cap is necessary, clean the outside of the reservoir on and around the cap prior to removal.

3.2.	With the rear brake pipe installed securely to the master cylinder, loosen and separate the front brake pipe from the front port of the brake master cylinder.

3.3.	Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder.

3.4.	Reconnect the brake pipe to the master cylinder port, and rotate the line at the master cylinder at least 30 degrees, so that the line will be positioned BELOW the MAX fill line on the brake master cylinder reservoir. Tighten the line nut securely.

3.5.	Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the pedal.

3.6.	Loosen the same brake pipe to purge air from the open port of the master cylinder.

3.7.	Tighten the brake pipe, then have the assistant slowly release the brake pedal.

3.8.	Wait 15 seconds, then repeat steps 3.5-3.7 until all air is purged from the same port of the master cylinder.

3.9.

With the front brake pipe installed securely to the master cylinder - after all air has been purged from the front port of the master cylinder - loosen and separate the rear brake pipe from the master cylinder, then repeat steps 3.5-3.7, ensuring that the line is rotated below the master cylinder MAX fill line.

3.10.

After completing the final master cylinder port bleeding procedure, ensure that both of the brake pipe-to-master cylinder fittings are properly tightened, and that they remain in their new rotated positions below the MAX fill line of the brake fluid reservoir.

4. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme 11® GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.

Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and diaphragm.

5. Install the J 35589-A to the brake master cylinder reservoir.
6. Check the brake fluid level in the J 29532 , or equivalent. Add Delco Supreme 11® GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container as necessary to bring the level to approximately the half-full point.
7. Connect the J 29532 , or equivalent, to the J 35589-A .
8. Charge the J 29532 , or equivalent, air tank to 175-205 kPa (25-30 psi).
9. Open the J 29532 , or equivalent, fluid tank valve to allow pressurized brake fluid to enter the brake system.
10. Wait approximately 30 seconds, then inspect the entire hydraulic brake system in order to ensure that there are no existing external brake fluid leaks.

Any brake fluid leaks identified require repair prior to completing this procedure.

11. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
12. Install a transparent hose over the end of the bleeder valve.
13. Submerge the open end of the transparent hose into a transparent container partially filled with Delco Supreme 11® GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
14. Repeat steps 11-13 for the LEFT FRONT wheel hydraulic circuit bleeder valve.
15. Loosen the bleeder valve to purge air from the wheel hydraulic circuit. It is important that both bleeder valves be open at the same time. Allow fluid to flow until air bubbles stop flowing from the bleeder, then tighten the bleeder valve.
16. With the right rear and left front wheel hydraulic circuit bleeder valve tightened securely - after all air has been purged from the right rear and left front hydraulic circuit - install a proper box-end wrench onto the LEFT REAR and RIGHT FRONT wheel hydraulic circuit bleeder valve.
17. Install a transparent hose over the end of the bleeder valve, then repeat step 15.
18. After completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4 wheel hydraulic circuit bleeder valves are properly tightened.
19. Loosen the rear master cylinder jumper line nut slightly (just enough to rotate the line), and rotate the rear master cylinder hydraulic pipe back to the original position, and tighten the line nut.
20. Reposition the front master cylinder jumper line to the original position in a similar manner to step 19.
21. Close the J 29532 , or equivalent, fluid tank valve, then disconnect the J 29532 , or equivalent, from the J 35589-A .
22. Remove the J 35589-A from the brake master cylinder reservoir.
23. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme 11® GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
24. Slowly depress and release the brake pedal. Observe the feel of the brake pedal.
25. If the brake pedal feels spongy perform the following steps:

25.1.

Inspect the brake system for external leaks. Refer to Brake System External Leak Inspection.

25.2.

If equipped with Antilock Brakes, using a scan tool, perform the antilock brake system automated bleeding procedure to remove any air that may have been trapped in the BPMV. Refer to Antilock Brake System Automated Bleed Procedure.

26. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp remains illuminated.

Note: DO NOT allow the vehicle to be driven until it is diagnosed and repaired.

27. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes.