You said it sat for a while. Did you dump the old gas or just add to it? First things first dump and flush any old gas out. Check if the fuel tank is rusted in the bottom.
There are a number of problems you could be having. Vacuum lines come off the carb/intake not the head. There is two. One goes to an automatic valve(auto cock) on the bottom of the fuel tank. When vacuum is applied, the valve allows fuel to flow into the carb. Check both the fuel supply line and the vac line coming off that auto cock. Check both for leaks or clogs. Then pull the vac line and fuel supply line off the carb end. With fuel in the tank suck on the vac line(promise you won't get gas in your mouth
). Fuel should flow out of the supply line when you suck on the vac line. If not the auto cock could be bad or clogged.
Depending on how bad the fuel was you may need to go through and clean/replace the entire fuel system. Lots of rust is bad. Severe rust in the tank and carb is very bad. If it's not too bad, Clean the tank and carb, then replace fuel lines, fuel filter, and that auto cock($25 or less). If there's no rust or deposits in the tank then you may be able to get away with just flushing the tank once or twice, blowing the lines out, and a good carb cleaning.