DIY Brake Fluid Flush/Bleed
 

After replacing my brake booster; Full details on that issue here:
https://mbworld.org/forums/mercedes-tech-talk/220776-help-brake-booster-problem.html

...I had to do a brake bleed/flush. Months back I had purchased a Motive Power Brake Bleeder from Performance Products. For once, a tool works as advertised.


Here's a summary of the steps for my CL (W215):

DISCLAIMER: This is my experience with my own vehicle. Braking systems are a critical component to vehicle safety. If you are not comfortable with this procedure, have a qualified mechanic perform this for you. I am assuming no responsibility with the outcome on your vehicle. Perform at your own risk.


Tools:
Turkey Baster (No kidding)
Aluminum Cooking Tray (Again no kidding)
Motive Power Bleeder and bleeder nipple hose
1L of DOT4 Brake Fluid. I used ATE Super Blue (I bought 2 but it was excess)

1. Get the car on jack stands and remove tires.

2. In the engine bay, open the brake fluid reservoir and using the turkey baster, remove all dirty brake fluid.

3. Pour in some fresh brake fluid and keep it slightly under the full mark.

4. After cleaning and drying the Motive Power Bleeder (alcohol), pour the remaining new
brake fluid into the Motive bleeder.

5. Screw the main top back on (the one with the hand pump) and screw on the end of the hose with the reservoir cap attached to the reservoir.

6. Slowly pump the power bleeder and look out for leaks. Do not exceed 20PSI. I only brought it up to 10PSI and it worked fine for me. I was in no rush. If you over pump, you run the risk of ruining the seals in the master cylinder. Be careful.

7. After pressurizing the system to 10PSI, starting from the farthest caliper from the master cylinder (right, rear) remove the bleeder cover and expose the bleeder nipple.

8. Attach the bleeder nipple hose to guide the old brake fluid into a suitable tray. Using a wrench, release the bleeder valve. Brake fluid will begin to flow out and maybe with some bubbles.

9. Continue to bleed until fresh fluid begins to flow. Since I used ATE Super Blue, it was easy for me because the color changed from Amber to Blue.

10. When fresh fluid begins to flow, seal off the bleeder valve, remove the bleeder nipple hose and recap the bleeder nipple. Repeat this procedure on all calipers starting from the farthest and ending up with the closest to the master cylinder. You will need to re-pump the pressure bleeder before proceeding to each caliper. Mine dropped from 10PSI to about 5PSI after bleeding each caliper.

11. When you're done bleeding, carefully unscrew the Motive power bleeder main cover (the one with the hand pump attached to it). Do this slowly as it is pressurized. Then slowly remove the cap attached to the reservoir. DO NOT GET ANY BRAKE FLUID ON YOUR PAINT OR SKIN. IT IS VERY CORROSIVE. FLUSH WITH WATER IMMEDIATELY IF SO.

12. Cover the reservoir, remove any excess brake fluid that may have dripped. Put tires back on, lower the car and test brake pedal action. You're done.

Any questions, PM me.

Thanks for taking the time to write this up. Great job! :zoom:

:y:D

Fantastic write up. Thank you. Guys like you give guys like me the courage to get a 17 year old Mercedes and then work on it. My local dealer wanted $490 to replace the fluid.

Nice !

or you buy auto valves from stahlbus and it will take you minutes

stahlbus