Need Help! Problems with Engine

[Jaakko K]

Hi

I have x30 2007 with 350 engine. When I try to start my boat it only runs 30 or something seconds proberly and then dies. It doesnt matter if the rpm are high or not. And if I try to start it straight a way it wount start or it is realy hard but if I try after 5 min it runs smoothly 30 and then dies.

I just changed our alternator and after that it run smoothly. We ha less than half tank fuel.

I was thinking that maybe the problem is in the fuel pump but I can hear some noise and shacking when I put the power on.

Any ideas guys any help would be much appreciated.

Jaakko