2003 350 EFI mag Frustrated and need help

[TilliamWe]

Re: 2003 350 EFI mag Frustrated and need help

Your 1983 intake will NOT fit the Vortec heads. And as mentioned above, your 2003 block may not even have a place for the mechanical fuel pump. If it does, then an intake manifold is your only other purchase.
You don't need a different wiring harness, as Merc engines are plug and play. The 2003 engine is plugged into your 1983 harness right now.

 

[electric b]

Re: 2003 350 EFI mag Frustrated and need help

I do have the frozen block 1983 engine so all the parts are still intact. I will need to check and see it the EFI engine has the fuel pump port. If it does then I should be able to get a after market manifold right? I also was planning on going back to the outdrive supplied cooling system and get rid of the sea pump. Any worries with cooling as I thought that was an issue with the vortech heads. Bottom line is I am done with this EFI system. I have a long block good 350. I have a frozen/cracked block mercruiser 350 and a freshly6 rebuilt 2003 350 with vortech heads and EFI TBI. It would be nice to be able to use the vortech heads and freshly rebuilt block with all the other components off of the cracked block. (exhaust manifolds,fuel pump,water pump,carb, maybe a new intake if it will not bolt up. Between the 3 engines I need 1 good one.

 

[TilliamWe]

Re: 2003 350 EFI mag Frustrated and need help

Well, until you actually know why this motor won't run properly, it seems silly to replace it or try to build another. It's almost got to be something simple. You haven't checked all the simple stuff, yet. Fuel tank vent is a real possibility, since the boat has been in storage for 4 years.

You did mention the fuel line being taken out of the tank to "check the screen". Well, at the top of the tank, where the fitting is screwed in, that's where the anti-siphon valve is located. That's also usually where that "screen" is located as well.

Not sure why you felt you had to modify the cooling system. Sure Vortec heads are thinner than the "older" heads, but not so much that the pump in an Alpha one drive wouldn't have cooled them. If your modified cooling system isn't working properly, is it possible that the Cool Fuel isn't cooling the fuel?