Might check the screen in the gas tank if it has one or the blow out the little hole at the bottom of the tank. Before you do it though take the fuel line off the carburetor so you can see if any gas is coming through the line. Might also check the fuel filter or the shut off valve if so equipped. I have also experienced a clasped fuel line from age that kept the gas from getting to the engine.
Hope this might help just my feed back and some of my experience I have had to deal with.
Sincerely,
Labrauer
