[reclinedrelic]

Holy thread resurrection Danman! Scroll down on this page. https://ofapars-.webs.com/fuelnair.htm Lots of other interesting stuff to explore on the website.

 

[reclinedrelic]

I don't see anything about the petcock there, though.
Of course, the whole problem can be eliminated by converting to a non-vacuum petcock.

If you are referring to Hann's site the page I gave a link for gives instructions on disabling the vacuum function, converting the petcock to non-vacuum type. I believe that is to what phantomcxmenace was referring.