[urq] Leaky Proportioning Valve

Eric Renneisen racingiron at comcast.net
Tue Feb 22 22:05:34 EST 2005

OK, a friend of mine had a used S4 G60 caliper and no need to hold any
really heavy doors open, so I replaced my nasty seized rebuilt one with
it.  As part of the process, I pressure bled the entire system, starting
with the MC and proportioning valve, and even the clutch slave (nasty
stuff came out of there!).

A quick test drive confirmed that the new caliper completely cured the
vibration under braking.  When I came back to the car a few days later,
I found a nice puddle of Ate Super Blue and a low reservoir.  The only
positive from this is that the epoxy floor made cleanup a snap.

The source appears to be the proportioning valve, probably the round
area next to the canister in the inset picture here:
Anything to be done about this besides replacing the whole unit?

Eric Renneisen
'94 S4
'90 CQ 20V
'86 urq
Chattanooga, TN

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