Small Engines (Lawn Mowers, etc.): B&S 6.5HP Engine, compression check, float bowl

Question
I have a Sears push lawnmower model (917-388751) with a B&S 6.5Hp engine, model (BSP-123K02-0181) that will not start. I did remove the carburetor and it was very clean. I blew all the passage ways out and re-installed it with new gaskets. I can prime it using the primer bulb 3 times or 50 times (doesn’t matter) and it will crank on the first pull and then it shuts back down like its not getting gas.  I can remove the spark plug and put a small amount of gas into the cylinder and put the spark plug back and it will crank with the first pull. It will only run for a couple of seconds and shut back down. I removed the head and there is no cylinder wear at all and the valves look good. Before I removed the head, I did a compression check and it was reading 70 psi. This mower is a couple of years old and hasn’t been run very much. Thanks for your help.

Thank You,
R.C.
[email protected]  

Answer
Since the mower will start when primed, then the compression, timing and ignition are fine.  The problem has to be with fuel delivery.

The float bowl nut should have a hole in the center.  Is this hole clean?  Is the fuel fresh?  Sometimes the carburetors need to be cleaned a couple of times to get them working.
Re-clean the carb and let me know what happens.
Eric