I have replaced the line between the needle valve and carb, as well as tightened all the fuel nipples on the needle valve and carb. The back plate was real tight as well, with allen type bolts. I flushed the needle valve with alcohol, but did not blow it out. The bulkheads are designed in such a way so that the tank is held snuggly in place, so I am not sure it is a foaming issue.

I will try to blow out the hairs in the needle valve and replace the fuel line going from the tank to the needle valve. I will check the clunk as well. I will let you know if that works.

Thanks, Mike