[quote author=mwd link=board=1;threadid=7666;start=msg64468#msg64468 date=1069126690]
Yes, it starts out with fuel up halfway in the window.
This is a rebuilt carb, a few months ago.
I have tried leaving the gas cap off. I have tried pulling the hose off that goes to the carbon cannister.
Out of ideas!! Wondering about the fuel pump, it should provide a check valve function. Maybe I should pinch off a hose close to the fuel pump to see if that helps.
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It isn't going to siphon back out of the inlet or the vapor return. If it isn't siphoning into the venturi, it may be boiling out if the cooling fan isn't working. Take the air cleaner off and see if it is dripping after you shut it off. It is a common rebuild mistake to forget to blow out the air holes in the top cover. I like to check whtm with a piece of nylon fishing line.