Leaking Prop valve

[Cautrell05]

Been having issues with leaking proportioning valves on multiple vehicles. One is a 65 Impala with a power disk conversion and the other is a 64 C10 with the same conversion. The Impala has had 3 different valves on it now. So far the third is holding. The 64 Pu came in the shop this morning leaking from the same place. I dont like this pattern. Is there a better source to get them from? The impala kit came from classic industries and the Pu kit came from Classic performance products. All of them have been leaking from the rubber plug on the front end that covers the little metal button. Any ideas here?


Thanks
Nick

[Cautrell05]

This is where they all have been leaking.

[racecougar]

Wilwood offers a quality adjustable prop valve that would drop in place.

[dennislbrooks]

Well, I had the same problem on a near new prop valve from Speedway on the 42. It is an easy fix but it is sad that many of them do the same thing on these generic type valves. It is because of they're manufacturing clearances. Leave on vehicle, catch the drips, remove the nut behind the rubber cap -- look at the seal method---I have not had one apart in a while but I used the smallest/thinnest of rubber orings ( like 1/4" diameter or so) to increase the pinch (push) of the nut. Test with a heavy foot in drive way. I have had no problem or leaks for over 5 years.