I am having problem bleeding the back brakes.

The brake fluid is not flowing from the reservoir to the back chamber of the master cylinder. It does for the front.

When I bleed the back brakes the fluid level does not go down.It does for the front

I have replaced the master cylinder.

How can a brake reservoir go bad?

You have to overfill the reservoir to get fluid into the rear portion. The hole in the reservoir for the rear chamber is at the top and is small. Just keep pouring untill you see no more bubbles.


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Benzmac:
Donnie Drummonds
300E
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM
OWNER OF MB AUTOWERKS .COM