Re: Brakes went potty

Posted by HH56 On 2012/10/27 23:00:54

If the fluid is clear you can see the top of valve right in the center of reservoir by shining a flashlight and looking thru the fill opening. A small piece of wire stem surrounded by a conical spring. The blob of rubber is under the threaded plug which contains the assembly and won't be visible from the top.

The compensator valve or blob of rubber is not the cause of eating fluid. If the valve fails, you have no brakes period. The pedal goes all the way down to the floor because the fluid instead of being sealed in the master under pressure to go to wheel cylinders leaks back into the reservoir instead.

If fluid is disappearing and any external leaks ruled out, it is most likely being forced or being pulled into the vacuum side. There are two seals surrounding the piston. Apparently they have hardened, worn or cracked or else the casting surface or piston shaft has developed pits in the area where the seal normally sits and fluid is leaking around them. To replace will require complete disassembly of the unit.