Proportioning valve leak

[Jk918]

I have a proportioning valve in the rear brake line, it is new but has a very faint seepage leak that doesn't drip, but shows on a clean paper towel where the adjustment knob o ring is (yellow). I've tried to tighten as tight as it could, tried new o ring, even tried a flat style rubber washer. Is there a secret to get it to stop, any pointers would be appreciated

[boss_hoss]

I bought a Wilwood one just like that and had a similar problem almost immediately. unfortunately what I was able to surmise is that the aluminum Wilwood uses on that particular prop valve is pretty soft which results in either threads getting mangled or the mating surfaces where the various parts go together can get deformed by over tightening causing leakage issues. I ended up switching to a Baer billet proportioning valve and have had no issues since

[Jk918]

Yeah I see that, likely the same issue i am having. I'll look for a different version, appreciate the feedback and solution.

[vcho455]

Oh great I just installed one of those!