Over the weekend, I started the engine for the first time. No major problems, other than the usual issues (180 out dizzy and timing). After running for a while, I shut it off, then closed the garage. When I came back a couple hours later, it smelled of gasoline. It does not seem to be coming from the tank vent, although I am going to make a charcoal filter for that. Instead, it seems to be coming from the air cleaner. So I am wondering if this is normal, or if I need to check something in the carb (perhaps gas is still getting pushed into engine after it is shut off from the residual pressure)???