Fortunately the OP solved his problems in time to till his garden this spring, but this is a good place to compare notes. This spring I couldn't figure out why my welder/generator wouldn't run; there was plenty of fuel when I pulled the line off the tank, yet the fuel filter wouldn't fill up. The lines were new, so that wasn't the problem. I finally talked to the small engine guy who keeps me running... I hated to bother him but was at my wit's end. It turns out that the rubber tip of the needle valve was old and swollen, so that fuel couldn't flow through. He changed that and I was up and running.