2005 4.3 mpi efi

[soonerborn1]

Bought the boat this year, the boat starts and runs fine but when I shut
down and sit for a bit, when I start the boat the engine runs rough then dies.
After sitting for a while letting the engine cool down, the engine will start and run fine again. If I shut down after running for a while and then start right away, its fine. Only if I let sit for 30 or so minutes do I have the problem. The pump is priming when I turn key but there is a different sound to it when it finally starts and runs good. Is this a vapor lock issue?Could the pump be going bad? I have changed the filter and fuel pump relay but did not fix.

 

[soonerborn1]

Re: 2005 4.3 mpi efi

Anyone have any Ideas?

 

[Don S]

Re: 2005 4.3 mpi efi

Is it hot in the engine compartment?

Have a look at this Merc service bulletin, it may help you find and fix your problem.

http://www.boatfix.com/merc/Bullet/99/99_07.pdf

 

[soonerborn1]

Re: 2005 4.3 mpi efi

Thanks, yes it does get pretty hot. I have tried idling for about 10 min with the engine cover up. After shutdown I also left cover up for about 30 min.
Still did not fix the problem. Eventually it does start and run fine after about an hour.

 

[soonerborn1]

Re: 2005 4.3 mpi efi

Does anyone know where the fuel pump is locatated on this thing?