Convert 4.3 Truck motor to Marine? need advise please

[propmonster]

Ok here's the story, just bought an 1992 Thompson Carrara 2000, (boat and trailer for $300.!) the boat come from CT and believe it was salt water use. The motor had already been torn down, heads off, and has sat outside, uncovered, for awhile, so just assuming junk. I do have all the components from motor, intake, carb., manifolds, alt. etc.
So this is what I need to know, I have a good ruuning, low milage 4.3 out of a 2000 S-10 pick-up. Can I swap the marine parts, starter, alt., intake-carb etc. onto this motor and use it? Will I need to change cam? Of course on a tight budget and just want to get on the lake as cheep as possible. Note; boat will be inland lake fresh water use.

thanks in advance for advise

 

[tpenfield]

Re: Convert 4.3 Truck motor to Marine? need advise please

The cam in an S-10 might be something to look into, but generally, you can do what your are planning. Swap out the regular core plugs to Brass core plugs.

 

[Silvertip]

Re: Convert 4.3 Truck motor to Marine? need advise please

The cam in the S-10 will be fine. These engines were torquey just off idle to the top end so it will work well.

 

[Bondo]

Re: Convert 4.3 Truck motor to Marine? need advise please

Can I swap the marine parts, starter, alt., intake-carb etc. onto this motor and use it?

Ayuh,.... Welcome Aboard,... Sure, it's usable that way,...

You'll need to go to an electric fuel pump though, the newer block ain't drilled for the mechanical pump,...

 

[propmonster]

Re: Convert 4.3 Truck motor to Marine? need advise please

Thanks guys, this is just what I wanted to hear, it will save me a ton of cash. I haven't really tore into this too much yet, been too busy with work, but the carb that was laying in the boat looks to be a TBI and it appears there is a inline electric fuel pump? Would this have been a TBI motor in 92? Really appreciate the help, hoping to do the swap next week and be in the water for the 4th, LOL!

 

[matt167]

Re: Convert 4.3 Truck motor to Marine? need advise please

Hold on... Automotive 4.3L engines changed in 1993-1994 or so and then again in 1996. The difference has to do with balance shaft/ non balance shaft and the Vortecs came in 1996. Just make sure the engine is what you need because you can't swap the parts from one to the other.

 

[propmonster]

Re: Convert 4.3 Truck motor to Marine? need advise please

I wondered about the whole vortec change, I know the heads are different, wasn't sure if an older style intake or exhaust manifolds would work or anything else for that matter. Another thought would be to just use the engine as is, and put marine alt and starter on it, I still have the whole truck (wrecked) with harness, computer etc. Might just have to find Votec exhaust manifolds and risers if they are different?? I know it would just be easier to buy a drop in ready marine motor, but they are hard to come buy used in my area, and when I do find them you would think they had gold plated blocks! $$$

 

[thumpar]

Re: Convert 4.3 Truck motor to Marine? need advise please

You will need to buy a vortec intake for a carb or use the old heads and intake.

 

[matt167]

Re: Convert 4.3 Truck motor to Marine? need advise please

Exhaust is the same, you can use the '92 heads to use the marine intake and distributor you have. The problem may come that the '00 engine is a balance shaft engine and the '92 is not. IIRC there is also 2 variations of balance shafts and they do not interchange.. If the engines match you can use it.. Between balance shaft and non balance shaft engines, it's supposed to be able to be swapped by changing the timing covers and removing the shaft but I do not know if they are internally balanced with the balance shaft in mind or not.

 

[propmonster]

Re: Convert 4.3 Truck motor to Marine? need advise please

Oh boy! This is starting to sound just as complicated as I first feared, because like I said, I bought it abandon with the motor tore down and exposed outside for who knows how long, heads were very rusty along with the rest of the block, didn't want to try and use any of that. Electronics, alt., intake, carb and distributor were in cuddy and protected so thats all I have to work with. Starting to think I will just sell the truck motor to offset the cost of a marine replacement, I don't want to trust some Franken-Engine to cross the Straits with . Thanks for all the info guys!! Thought it was worth a shot.

 

[matt167]

Re: Convert 4.3 Truck motor to Marine? need advise please

The marine engine is just a truck engine that Mercury marinized. They do use a different camshaft but truck cams are close enough. All you need to do is match the engine with one that does or does not have a balance shaft. Pretty sure yours is non balance shaft ( If the timing cover is a standard SBC cover, it is non balance shaft ). So limit your searches to 1987-1992 motors or whichever looks right..

I just checked Car-part and it looks like 1987-1992 engines are interchangeable in the full size trucks. Your 1992 boat most likely has a 1991 date coded engine so you should be good to use about any 1987-1992 4.3L