1999 E280 No rear brakes!

[gasket]

Hi all i have just become a first time MB owner.
The problem is the car has no rear brakes at all.
I have fitted a new master cylinder and no matter what i do it will not bleed
but the front brakes bleed perfectly.
Any suggestions?

 

[wireman]

Have you tried a pressure bleeding kit?

The master cylinders pistons must return fully back too allow fluid to enter the system from the reservoir. Since the inner workings of a tandem piston cylinder have a very slight clearance between the pistons it may be that the rear one is covering its pilot hole and the front one still has its open, this might be due to very slight input rod protrusion from the pedal/servo assy.

It might be the wrong master cylinder, or if it can be adjusted the pedal to servo link requires adjustment.

 

[hardtop]

did you use the right bleed sequence i think its REAR-RIGHT-REAR-LEFT-RIGHT-FRONT-LEFT-FRONT

 

[wireman]

Its rears first lh front rh front. You do the brakes farthest away first.

If (with it all working correctly) you do the front first a tiny quantity of air can become trapped between the two master cylinder pistons and you get a slight softness to the pedal feel.

If there is a problem like the one I outlined previously there may well seem be a little excess pedal travel and it will feel quite firm.

 

[gasket]

Well i got fluid up to the abs unit & it appears there is no fluid coming out of the other side to the rear brakes! ill think the unit may be u/s.
sounds expensive!