Mower cranks when primed, but after running a second or two dies?

I have a sears craftsman II model # 917 372 480 5.0hp, with the the 22" cut, front wheel drive model. Ok, here is the question, she was running like a champ and I hit something burried in the ground, and she quit. It will crank if primed, it will run until what I am assuming the gas from the primer runs out, but then dies. What could be the cause here? I have inspected fuel lines for holes, the blade spins well which turns the motor, and it also spins balanced, so I know it couldn't be the crank shaft bent to lock up. It pulls over fine, and if I add starting fluid to the spark plug hole she fires right up aswell. So, what am I doing wrong here, what have I not checked? I poured out all the gas, cleaned out the bowl, re-primed the bowl, cleaned the fuel line and filter...

Any help would be greatly appreciated

Corey
June 2010