Leaking Petcock & Repair Kit

I have read a lot about aftermarket petcock repair kits on these forums. Many have said they have put them in and the petcock still leaks. I bought a K&I kit for $30+ bucks. Installed it, and just like they said, the petcock still leaked through (worse) when place in the ON or RES position. (It should NOT leak in those positions.)

All indications would say the spring was the culprit because when you push slightly on the mechanism, the o-ring would seal, as verified when I blew through the fuel tube. Something was amiss because there was NO wear on the petcock inside.

Here is what I found: I measured the length of the new 'insert', the piece of metal with the new little o-ring on it. It measured .008 LESS than the OEM one, meaning if it's shorter, less sealing surface for the o-ring and less force exerted by the spring. So, I just put the new o-ring on the OEM 'insert' and used the new spring, and it worked perfectly. No leaks!

Not saying K&I makes an inferior petcock kit, just saying theirs measured .640 as compared to OEM's measuring .648. Maybe even a small washer would have worked with the K&I kit, somehow. But, I just used the OEM 'insert' with a new o-ring. Hope this helps someone. I was tired of fighting it and almost just bought a new OEM petcock. What's funny, and as it turned out, I paid $30+ for a tiny o-ring and a ten cent spring. At least it's fixed.