[wetdog]

Eyal , hey your almost there ! remember we got ours about the same time, I took my tank and welded a male an fitting to it ..well the tank was FULL of crap pine needles , moths, stickers, and weld slag it was horrible if I had hooked it up we would have been in the same boat .
Take your tank down and look through the sender hole mine looked clean until I took a clean white rag taped to a rod and ran it around . Take it to a radaitor shop and for 30 bucks or so they will boil it out and pressure test as well ...good luck If that is the problem your carb is messed up as well ..WD