take the air filter off and put some fuel right in the carb, it should fire up, even if its just for a second. then you know its a fuel problem and start looking at your lines. You could be sucking air if one of your lines is cracked. Fuel filter or pick-up could be plugged. But see if it will run on the direct injection through the carb first, to see if it is indeed a fuel problem and not something else. We'll go from there.
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