How To Flush And Bleed The Brakes
The pump is a fluid pump and needs to be initially bled to get the air out of the pump. The pump will not work with air in it. Once the brake pump has been off the car, or ran without fluid, it will be air bound and the brake pump will need to have the air purged from it before bleeding rest of the brake system. Here are instructions for purging air from the pump.
- 1. Any time the brake hydraulic system is to be opened the brake pedal should be pumped 25 times with the key off to bleed off the 2600 pounds of pressure in the accumulator.
- 2. Siphon out as much of the old fluid as possible from the reservoir and refill with clean fluid to the top. Another good way is to remove the rubber hose that comes from the reservoir right where it attaches to the ABS pump and let all the fluid in the reservoir run out.
The plastic fitting the hose connects to can be easily broken. If you have trouble removing the hose, cut the rubber hose that comes from the reservoir close to where it attaches to the ABS pump. Then remove the piece of hose still attached to the pump fitting and reinstall the rubber hose. It is long enough to do this.I like to cut it rather than try and remove it because the hose sticks really hard to the plastic fitting and you might break the fitting trying to take the hose off. Doing it this way you get all the fluid out of the reservoir before putting in new clean fluid.
- 3. When doing the rear wheels only let out about a half of a cup and then refill the reservoir. This is to make sure you don't take out too much and get air into the system.
- 4. To bleed the front brakes have the key off and bleed in a conventional method. Have someone pump the pedal a few times and hold it down while the other person opens the front bleeders.
The rear calipers on models equipped with the Teves system require a slightly different procedure to bleed the air from the system.
- 5. To bleed the rear brakes
- A. Turn on the key and allow the system to pressurize
- B. Have an assistant slightly depress the pedal and hold it.
- C. Open each rear bleeder, one at a time, and hold open until clear fluid comes out. (The pump and motor will do the bleeding)
- Close the bleeder with sufficient force but do not over-tighten.
When you are done check the high and low marks on the reservoir. After the system pump and motor has run and the lights are out the level should be at the low mark. When you have pumped the brakes with the key off 25 times the level will be at the high mark. Add or remove fluid if necessary to bring the fluid to the correct level.