swap a 4 cylinder for a 6

[mike64646]

1992 bayliner trophy. Owner wants to sell but is out of state from me. Can't tell me if its a 4 or 6 cylinder, all she knows is that the motor is "seized up". (She must have gotten it in a divorce settlement? )
Before i drive 6 hours to see the boat, I'd like to know that IF the existing engine is a 4 cylinder (volvo or chevy or whatever) can I can drop a 6 cylinder in there without tooooo much of a hassle? I want to put it on Lake Erie but I want more than 4 cylinders if and when I need to get off the lake in a hurry or plow through some swells.

Also, its a salt water boat, going to fresh water. Do i have to change the outdrive to put a freshwater engine in (no radiator)? Do saltwater outdrives have water intakes? Its a great deal if I can make these adjustments.

Thanks

 

[NYBo]

Re: swap a 4 cylinder for a 6

Welcome to iboats!

Sorry, there isn't enough info here to give you a precise answer. In general, there is a LOT involved in making such a swap.

You are a bit confused about saltwater vs freshwater engines. There are raw water cooled engines and freshwater cooled engines. The latter name is misleading; it uses a closed cooling system for the engine, filled with antifreeze and employing a heat exchanger. Either type can be used in either salt or fresh water. How's that for confusing?

A simple picture of the engine compartment would answer a lot of questions (V6 vs I4, raw vs fresh water cooled, brand...)

 

[mike64646]

Re: swap a 4 cylinder for a 6

Thanks for your reply; i guess i was wondering, too, if the manufacturer made different sized engine compartments for different sized engines; would a 6 cylinder or even a V-8 fit in a compartment that came stock with a 4 cylinder in it, nevermind motor mounts, or do I have to change out the outdrive top match the engine or are they standard across powerplants, etc.

 

[howlnmad]

Re: swap a 4 cylinder for a 6

To change from 4 cyl to 6 cyl will require an outdrive change due to different gear ratios.
If the cooling system is raw water, the only change from salt to fresh water would be the t-stat. Saltwater uses a cooler one than fresh.
Engine compartmwnts are pretty much boat specific. My cuddy has a 4 cyl in it but will fit a small block V-8.