Best engine replacement

Been searching this site as well as others for information on putting a 2005 5.7 hemi into a boat. Since there is no threads found on this (other than "why no Hemis") this is a bad idea. I do have a garage that will trade the Hemi for either rebuilding a 1998 Dodge 5.9 from a pick-up into a marine engine or trade for a rebuildable mercruiser (old Ford engine). Not sure the trade is worth it. Would like to hear your thoughts on this. (Bayliner 25 ft HAD NO ENGINE when purchased) Told the boat had a 302 in it before I got it.

Re: Best engine replacement

Where are you going to get all the marine parts for that engine? Make them? The complete fuel system and electrical system has to be designed to keep you from blowing up or catching fire because of fuel leaks and open sparks.
Then there is the exhaust system. You need a water cooled exhaust system in an enclosed engine compartment. There aren't any for that engine.
Then you have the flywheel cover that is normally the rear engine mounts for any marine engine, none for that engine.
Coupler is the same way.

Bayliner has been making 25' boats for 30 years, what year is yours? and what drive or transom shield if any does it have.

Re: Best engine replacement

By Hemi, do you mean a Chrysler marine engine?

"hemi" is nothing more than a trademarked marketing term owned by Chrysler. No modern engines have a hemispherical combustion chamber anymore.
There were lots of Chrysler marine engines in the 60's and 70's. The 318/340/360/440 were probably the most common, but I think a 426 Hemi was also marinized. Probably the 392 too.
Chrysler even had their own outdrive.
Chrysler got out of the marine game back then. I don't think Chrysler has an industrial products division like GM does anymore.

GM sells industrial engines and drivetrain components to marine, medium duty equipment, generator set manufacturers etc... Chrysler doesn't. They aren't marketing to that game, because the customers aren't generally dissatisfied with the Chevrolet based stuff. You would need a pretty sharp pencil to try to compete... see Toyota and VW who backed away from the recreational marine market in more recent times.

So, as Don said - there' s no exhaust manifolds, compatible bellhousings etc... all heavy cast iron and cast aluminum parts that don't exist. You can't really make your own realistically.

If you want to put a 392 or 426 Hemi in a boat, I think that would be doable with a lot of searching. You can surely find a vintage boat for sale with Mopar power.

Re: Best engine replacement

First you blow up, then you catch on fire because of it . . .

Chrysler/Dodge has not made engines for the marine industry . . . at least for I/O's that I am aware of. Soooo, it would be unlikely that anyone (garage or individual) could make a marine version of the Hemi engine. Like Don says, the parts just do not exist.

If there were such a thing, many of us would be running around saying "and it's gotta Hemi in it"

Re: Best engine replacement

If the Bayliner hull is worth saving, post a pic of the cutout in the transom. It's probably Volvo Penta or OMC Cobra cutout - figuring out which will help you search for an entire driveline from carb to propeller that will mount in the opening.

Re: Best engine replacement

as I stated the idea of the 5.7 (2005) hemi will not work, Why I searched these threads. As far as the engine he says he can convert its a old Chrysler block. Hes a marine shop so I trust he knows what he is doing in a complete rebuild and finding all the right parts. Restating the question, I can buy a new marine engine that is a replacement engine (Ford 302 Mercuriser) or have this shop rebuild an old chrysler block either way he takes the 2005 Dodge 5.7 Hemi as payment. Repowering with a GM engine not going to happen.

Re: Best engine replacement

Well, a 5.7 Hemi is worth way more than a 302 Ford. But in the marine world, everything costs more. But why are you insistant on repowering with an obsolete engine? Don S will know better, but if the boat was a Mercruiser, (even one with a Ford engine) putting a SBC in it is going to be the least expensive and least painful option. And even if the boat had a Volvo Penta (or even a real OMC Cobra) repowering with a Chevy might still be the easiest way. But good luck to you.

Re: Best engine replacement

Do you realize that pretty much every I/O boat built in the last 15 to 20 years has had a GM engine? Ford's haven't been used in a long time. Sure, you can put one in, but why? Parts will be nearly impossible to find and expensive. Technicians to work on the engine will be the same way. With a standard, GM based Merc. or Volvo engine and drive you can have just about any marina in the country work on the engine and probably have the parts on hand.
If you ever try to sell the boat it will be worth a lot less with a custom designed (read hard to service) engine that no buyer will recognize as being desirable.
I would just put in a Merc. or Volvo and go boating. If it's a brand loyalty issues I understand, I refuse to own a Ford. However, I've had nearly perfect service from every GM product I've owned in the last 20 years.