MASTER CYLINDER......to REBUILT?
 

Hi,
After changed front rotors and brake pads my brake pedal is spongy...it was like this before and even after a good bleed and many miles to breke-in the new pads and rotors the sitiation is the same.......car is CLK 430 and i would like to know if i have to change the master cylinder or if i can order just the repair kit.
Many thakns guys
Alberto

Hard to believe you've got a master cylinder problem on a car that new already. How id you bleed the brakes? Did you use a preessure bleeder? When you say it was like that before you changed the pads and rotors, had you already bled the system and that's when it got spongy?

Len

Bleed
 

Hi Len,
the brake pedal was like this 2 yera ago when i bought the car........baut may it become worst a little bit every days so......difficult to understand.
I bleed the system whitout the pressere system but i did this with my father in the car pushing the pedal and opening and closing the purge at right time.
I did this since many years on many cars and had already woirking.........
May be this system is not working with mB and i need a pressure or vacuum system....
Thanks
Alberto

I don't think you can use a vacuum system to bleed ABS brakes. I'd sure try a pressure bleed before throwing parts at the problem. I recall seeing that a Mercedes ABS system needed 30psi to bleed properly.

Len