Brake problem 86 190e

[Lurch]

Had the master cylinder replaced about 6 months/2,500km ago with brakes working fine until yesterday. Suddenly the pedal goes to the floor with braking power non-existant until the last half inch or so. Car will stop without problem from moderate speed (25 - 35 mph) but I really don't want to tempt fate with higher speeds. From the feel of it, I doubt there is enough grab to lock the wheels and again I don't wish to tempt fate trying, and then finding additional damage from doing so. Brake fluid reservoir is still pretty much full. Pumping the pedal results in no discernable change in feel or reservoir level.

Any ideas on what i should be looking for to zero in on the problem would be appreciated.

TIA

[autozen]

Those reservoirs can be deceiving. The front part is the rear brakes and the rear is for the front. I suspect that the rear part of the reservoir is out of fluid. Check for a problem at the front brakes and check for leaking seals at the bottom of the reservoir. Just my observations after 30 years as an MB mechanic. Take it or leave it.

peter

[Lurch]

Originally Posted by autozen

Those reservoirs can be deceiving. The front part is the rear brakes and the rear is for the front. I suspect that the rear part of the reservoir is out of fluid. Check for a problem at the front brakes and check for leaking seals at the bottom of the reservoir. Just my observations after 30 years as an MB mechanic. Take it or leave it.

peter

Thanks Peter. I'll take a look this evening and report back.

Patrick

[Lurch]

Have inspected brake fluid reservoir (no front/rear compartments) and it is full of fluid and there are no signs of leakage visible.

With engine idling I did pump the pedal rapidly and felt a build up of pedal feel before the engine revs dropped to the point of stalling the car. Throttling up to just above 2,000 rpm, I was unable to get any sort of pedal feel from pumping the brake pedal, however when i dropped back to idle, I was able to "tease" the revs down to just over the stalling point by pumping the brake pedal, at which point there was some resistance felt.

Any other troubleshooting tips would be gratefully accepted.

[mctwin2kman]

First thing you should do is bleed the brakes! Air may have gotten in there! Check all lines for leaks as well! Then last the vacuum line to the brake booster!

[csnow]

Despite being very new, it still smells like the Master.