sounds like your carb might not be pumping gas. Look down into the throat of the cab and pull the the carb linkage. If you don't see any gas squirt inside the carb then you probsbly have some trash in the bowl of your carb or your carb pump went bad. I had the same problem once. As long as I was pouring gas down the thraot of the carb the engine would run. I ended up just replacing the carb.
