3.0 question

[38special]

I bought a 1978 18' Marquis Stingray with the understanding the block was cracked and it is. It has a 120 Mercruiser in it and another boat i am thinking about buying has an engine that says OMC 3.0 with a mercruiser sterndrive. Is there any reason the OMC 3.0 with mercruiser sterndrive would not work in my boat? The OMC or the mercruiser sterndrive is a late 80s. Is the 3.0 OMC a GM marine engine?

 

[Bondo]

Re: 3.0 question

i am thinking about buying has an engine that says OMC 3.0 with a mercruiser sterndrive.

Ayuh,... Welcome Aboard...

Your getting into Mixin' & Matchin' that even I wouldn't try to pull off....
OMCs,+ Mercruisers Don't mix well...

 

[38special]

Re: 3.0 question

His boat is on craigslist about 2 hours drive from me. I asked him to check the engine out good for any cracks and he called me back last night and said the engine is painted blue with OMC 3.0 on it with a late 80's mercruiser outdrive.

The price is right but i don't want to run into any problems putting it in my 78 stingray if the engine is not a match to a Mercruiser 140. I guess i will leave it alone. Thanks

 

[crazyinkc]

Re: 3.0 question

The long block should be the same. You may need to swap manifolds but if someone already mated an alpha to it then I would assume that has already been done. They may have used the OMC manifold and re-engineered the exhaust to make it work. If the price is right, I don't see a problem.

 

[Fishermark]

Re: 3.0 question

I too would think the block can be swapped over. Since you already have the 120, you will also have some other externals you can swap over if necessary.

 

[38special]

Re: 3.0 question

The long block should be the same. You may need to swap manifolds but if someone already mated an alpha to it then I would assume that has already been done. They may have used the OMC manifold and re-engineered the exhaust to make it work. If the price is right, I don't see a problem.

I left message on his phone to write down engine specs and what mercruiser out put drive. I'm not sure what out put drive mine is on my 120 mercruiser. I think it's the original but it kind of sounds like i would have to use both his engine and out put drive to put back in my boat.

I'm new to all this and would like to limit my mistakes. Lol

 

[38special]

Re: 3.0 question

I too would think the block can be swapped over. Since you already have the 120, you will also have some other externals you can swap over if necessary.

Sounds hopeful. He is asking $350 for the whole boat but it's a 2 hour drive.

 

[38special]

Re: 3.0 question

Ayuh,... Welcome Aboard...

Your getting into Mixin' & Matchin' that even I wouldn't try to pull off....
OMCs,+ Mercruisers Don't mix well...

If the OMC 3.0 long block is the same as a certain year of Mercruiser 3.0 long block is there a problem if you find the right year of mercruiser out put drive that works on both other than maybe having to change a manifold or other external parts?

Again i am new to boats but have built engines all my life and it does not seem that big a deal if OMC and Mercruiser used the same engines with the same internals. Am i missing something here?

 

[Bondo]

Re: 3.0 question

Again i am new to boats but have built engines all my life and it does not seem that big a deal if OMC and Mercruiser used the same engines with the same internals. Am i missing something here?

Ayuh,... Then you clearly understand a Short block, vs. a Long block, vs. a Bobtail motor,..??
Not trying to insult you, but many posters Don't...

The commonality of the 2 motors in question relates ONLY to the Long block configuration....

Is there any reason the OMC 3.0 with mercruiser sterndrive

That doesn't exist in reality, except in some sorta Cobb Job....
Which is Why I answered the way I did...