Leaking Proportioning valves on master cylinder

[srgtlord]

One of my proportioning valves on my master  cylinder is leaking from the rubber o-ring. These little valves seem to be NLA. I did however find a source that sells them for the cabriolet and scrirocco but visibly appear different and cost $140... a peice. Is there a rebuild kit available for these little valves? Would the cabriolet proportioning valve work?

[thomas m]

Why not just get a new master? Not to suggest that you haven't thought about that, but I am curious.
Is a replacement not available for your model?

[srgtlord]

It's not the master cylinder that's leaking g, it's the canister looking proportioning valve that screws into the master cylinder that I can't find anywhere.

[vanbcguy]

Yeah there's a few models out there with a proportioning valve mounted at the MC. Most non ABS cars have the proportioning valve mounted under the car on the rear axle.

Cross compatibility between braking parts is always tricky, especially with things like that. Good chance a cabriolet part would work but it may change the brake bias. That's definitely an engineered part chosen for a specific reason.

What year/model do you have exactly? You might be able to retrofit a complete "common" setup.

Sent from my XT1097 using Tapatalk

[air-cooled or diesel]

did you try autohausaz? or partsplace, then again certain parts and more and more parts continually become unavailable. ?can also look for used ones; google 'used vw diesel parts' or in this case just 'used vw parts' may do,,gl.

[air-cooled or diesel]

so i do believe theyre 2 piece proportioning valves, the bottom has 2 slots for an open-end. so take them out; put bottom end in a vice, the top should take a wrench, see if its loose; if so thats your problem; you can now either tighten up ,,-or take apart and clean up, a new o-ring in there, and tighten; i dont think you can find a torque for this, although some where there may be one, tighten so it wont leak, i tighten some more(a little), i has to not leak for some while,,.

[srgtlord]

Well I ordered some brake fluid compatible o rings for about  $15. I'll report back when I install one

[air-cooled or diesel]

yea big difference between that and $140 per. hopefully it will do it.

[srgtlord]

Welp I ordered the wrong size o-ring...... I think I'm going to just break down and purchase the newer style proportioning valve and just set the height of the arm at a fixed position....

[srgtlord]

Well due to money constraints I begrudgingly  grabbed a proportioning valve off of my green vw golf that currently isn't registered. Problem solved.