lawnboy carb or engine problem

[meot]

Hey, I have a lawnboy 4.5 self propelled silver series lawnmower and I'm having a problem getting it started, I compleatly took the can apart and cleaned it with carb cleaner and made sure all the connections are right, I pull the cord on it but it won't start. It will if you spray carb starter but it won't stay running. The gas line is cleared and all the things are set in the right position and i just got a new float valve kit because the gas was pouring out of the fuel filter. What is wrong with it?

-Meot