Brggs & straton engine fuel problem?

I have a 5h.p B & S engine (dry bulb model) on my mower which will not start due to lack of fuel If I squirt fuel into carb inlet it will fire & then stop. There is a good fuel flow to the carb,which has all been cleaned out.Pumping the priming bulb does not have any effect either. I am using new fuel so it is not that. Any suggestions??