Small Engine Troubleshooting Problems? Ask a Mechanic Now.
The suction tube in the fuel tank has to be open, and it has to be capable of holding vacuum. Remove the tube and examine it and hold finger over one end while you suck on the other. It should hold vacuum. If it does, problem is fuel line or the fuel pomp. The fuel pump is what has t draw the vacuum and pull the fuel from the tank.
Do you have pulse going to the fuel pump while cranking, this would be the P line on the pump. If you have a pulse, do you feel suction on the fitting that goes to the filter/tank? No fuel coming out the carburetor line?