Hummer H3. Manual — part 1336

Bleeding Perocedure

1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills.

2. If you disconnected the brake pipes from the master cylinder, you must perform the

following steps:

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

NOTE:

Do Not allow the HBCi pump and motor to run more than 1 minute
continuously. Allow 2 minutes cool down time between pump run
times. Extended pump and motor run time could create excessive
heat and damage the pump and motor assembly.

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3

Fig. 44: View Of Master Cylinder And Brake Pipes
Courtesy of GENERAL MOTORS CORP.

2. With all the brake pipes installed securely to the master cylinder, loosen and separate

the left front brake pipe (4) from the left front port of the brake master cylinder.

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

cylinder.

4. Reconnect the brake pipe to the master cylinder port and tighten securely.

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3

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

the pedal.

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

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

8. Wait 15 seconds, then repeat steps 2.5-2.7 until all air is purged from the same port of

the master cylinder.

9. With the left front brake pipe (4) installed securely to the master cylinder, after all air

has been purged from the left front port of the master cylinder, loosen and separate the
right front brake pipe (3) from the master cylinder, then repeat steps 2.5-2.8.

10. Turn the ignition key to the ON position.

11. With the right front brake pipe (3) installed securely to the master cylinder, after all

air has been purged from the right front port of the master cylinder, loosen and
separate the right rear brake pipe (2) from the master cylinder, then repeat steps 2.5-
2.8.

12. With the right rear brake pipe (2) installed securely to the master cylinder, after all air

has been purged from the right rear port of the master cylinder, loosen and separate the
left rear brake pipe (1) from the master cylinder, then repeat steps 2.5-2.8.

13. After completing the final master cylinder port bleeding procedure, ensure that all of

the brake pipe-to-master cylinder fittings are properly tightened.

14. Turn the ignition key to the OFF position. Depress the brake pedal 20 times.

3. 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.

4. Install the J 44894-A to the brake master cylinder reservoir. See Special Tools.

5. Check the brake fluid level in the J 29532 or equivalent. See Special Tools. 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.

6. Connect the J 29532 or equivalent, to the J 44894-A . See Special Tools.

7. Charge the J 29532 or equivalent, air tank to 175-205 kPa (25-30 psi). See Special Tools.

8. Open the J 29532 or equivalent, fluid tank valve to allow pressurized brake fluid to enter

the brake system. See Special Tools.

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3

9. 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.

10. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder

valve.

11. Install a transparent hose over the end of the bleeder valve.

12. 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.

13. Loosen the bleeder valve to purge air from the wheel hydraulic circuit. Allow fluid to flow

until air bubbles stop flowing from the bleeder, then tighten the bleeder valve.

14. 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 REAR wheel hydraulic circuit bleeder valve.

15. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.

16. 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.

17. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.

18. With the right front wheel hydraulic circuit bleeder valve tightened securely, after all air has

been purged from the right front hydraulic circuit, install a proper box-end wrench onto the
LEFT FRONT wheel hydraulic circuit bleeder valve.

19. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.

20. After completing the final wheel hydraulic circuit bleeding procedure, ensure that each of

the 4 wheel hydraulic circuit bleeder valves are properly tightened.

21. Close the J 29532 or equivalent, fluid tank valve, then disconnect the J 29532 or

equivalent, from the J 44894-A . See Special Tools.

22. Remove the J 44894-A from the brake master cylinder reservoir. See Special Tools.

23. Fill the brake master cylinder reservoir. Refer to Master Cylinder Reservoir Filling.

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:

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

Inspection .

2. Using a scan tool, perform the antilock brake system automated bleeding procedure to

2007 Hummer H3

2007 BRAKES Hydraulic Brakes - H3