Motor will start easy after choking -----runs good for 5-10 seconds ----then runs out of gas -----gas tank fuel line is primed and bulb firm----when motor begins to die I can rechoke and leave choke plunger open and motor will run good at idle with earmuffs on lower unit ---- thought it was fuel pump ------but -have changed fuel pump from ANOTHEFR 30hp motor that is known to be GOOD ----the issue is is exactly the same. Gas tank has been cleaned and fresh fuel is being used. Thanx in advance for any help!!!!!!