Car Engine

Is it possible to take a car engine and put it in a boat? Can you make it marine ready? Or do you have to buy it specifically made for the water? I know it is a dumb question.

I know lots of people that have done it but some of the parts are marine specific

The exhaust is the biggest difference. There are many jet boats and hot boats that use automotive race engines in them. The core components for most inboard gas engines are car engine pieces, although usually the heavy duty versions.

obviously most of the cooling components are marine specific but also alternators, starters, thermostats, and oil pans are different as well and I believe the cams are different too and possibly the heads I could be wrong a couple of those listed but I think that's right . . . For the most part if you have say a 351 pcm that needs to be replaced do to a cracked block or something like that you should be able to buy a 351 windsor and swap parts off your bad engine and onto your new engine to make it work . . . . <---- I just woke up and I might not be making any sense but . . . there you go

(Message edited by lovin_the_wake on May 17, 2008)

They are heavy duty versions, truck blocks with four bolt mains if i remember right. Anything steel that comes in contact with with water is brass such as freeze plugs, pump internals and such. Cams are different as boat motors have totally different power curves.

I am getting the idea that it could be done by adding the marine specific parts to the block. Right?

Yes, you can marinize a auto block. That is what Merc, Indmar, and PCM do. The freeze plugs, cam, sometimes springs, fuel system, ignition system, and engine control module are different. Pistons, crank, bearings, and heads are all the same. It is not hard for an engine builder to accomplish, a bit harder for a backyard mechanic, daunting for the non-grease head.

Matt, what exactly are you looking at doing? Do you have a boat with a bad engine or a boat with no engine at all ?

merc uses GM blocks. its the same 350 thats in you chevy or GMC, just different cams and electrical stuff. Boat engines are different in that they run higher rpms. we call runnin 2500 rpms real high in a truck but thats about where a boat engine is cruisin at.

marine engines are great for mud racin trucks! just drop one in without changin anything and bolt a tranny up to it. That how i won my last 6 races. i just put a merc in my truck.

In dozens of Chevy 350s, auto, truck, and marine. They're identical. The marine engines are merely the truck, and or factory high performance engines. They have 4 bolt main bearing caps, found in trucks, Chevelles, Novas, Camaros....., they have forged steel cranks (sometimes), also found in cars/ trucks, and higher output camshafts, high performance/ truck rods, and double roller timing chains. Reverse rotation engines are the exception, having a gear drive rather than a timing chain, so that the distributor/ oil pump turn the right way, and the pistons are hung 180 degrees from norm. The only things that differentiate a "marine" engine from a GM factory truck/ high performance engine are the accessories, and ring gap, top ring gap in automotive engine-.035" top ring gap in marine engine-.080. It accounts for the higher piston dome temperature. You could pull a Mercruiser 350 out, swap the carb, ignition, alternator, etc.... on to a 350 from an '85 Silverado, overhaul it, regap the rings, and have the same thing you got from Mercruiser. End of rant.

Yeah we have a chevy 350 in our Donzi which was the same engine that was in our 69 impala until we got an a$$ kicker 502