RE: Pressure Relief Valve?

[Ron Mruss <rmruss@pangea.ca>]

[Ron Mruss]   Fred:  I'll be doing the brake servo test tomorrow.  Tonight I fitted a new cap for my reservoir which should help the overflowing - old one was broken.  Dealer wanted over $50 for the cap, I got it for $2 at the wreckers.

My pump isn't leaking, I just thought that perhaps there was a problem with my pressure relief valve and that's why the pump wasn't building up enough pressure.

If I ever figure this out, I'll let you know what the problem was.

Thanks again,

Jeff Mruss  
Jeff;

    If fluid is coming out of the top of the reservoir when you brake, it
sounds like your servo is passing fluid from the accumulator much faster
than the pump can pull it from the reservoir to fill the accumulator. This
is odd, though, because if the accumulator is fully charged and the
reservoir is filled to the "max" mark, completely discharging the
accumulator (by pumping the brakes with the engine off) will fill the
reservoir but not overflow it - I just tested this on my '91 200q after
replacing the bomb. In theory, the reservoir shouldn't overflow, although I
have seen posts on the "volcano syndrome" in which the overflowing reservoir
is the sign of a bad pump.
    Is your reservoir filled too full by any chance? Have you tried the
servo test to check the brake servo?
    Orin Eman posted on October 4 a description of his tussle with the
pressure relief valve. I have attached it for your convenience.

HTH
Fred Munro
'91 200q  262k km