2.5L 120hp swap to 3.0L

[cj8mule]

I just acquired an old boat that the PO let freeze. The motor model number is MCM 120 and is a 1978 2.5 liter. I'm pretty sure the outdrive is a MC-1.

Would a 1995 3.0 liter be a good candidate to swap in? Is it a direct bolt in swap even though the outdrives are different?

Is $500 a fair price for a '95 3.0 with 175 hours on it?

Thanks for your help

 

[Don S]

Re: 2.5L 120hp swap to 3.0L

Would a 1995 3.0 liter be a good candidate to swap in?

Yes

Is it a direct bolt in swap even though the outdrives are different?

No, things change after 20 years. Manifold and elbows for one thing.

Is $500 a fair price for a '95 3.0 with 175 hours on it?

If it's in good shape, yes. If it's freeze damaged or no compression and locked up No.

 

[cj8mule]

Re: 2.5L 120hp swap to 3.0L

Thanks Don. I'm a newby when it comes to the inboard outboard stuff and have never had one apart.

With everything that changed over those 20 years... I would need to use the outboard of that year? (Or however many years used that outdrive)

Do you happen to what years I should be looking for if I want a direct replacement?

**EDIT** It looks like 1967 to 1982 used the same outdrive.

 

[Don S]

Re: 2.5L 120hp swap to 3.0L

There is more to it than just the drive. Manifolds and elbow, and how they fit to the down pipe attached to the transom shield is the biggest problem.
Any time you start swapping different years, expect some problems. Unless you find some one that has done the exact swap (doubtful) you just never know what the little "Gotcha's" are going to be. Usually fixable, but not always. Just depends on the years .

 

[Conan87]

I'm looking to do the same swap, 1983 omc 2.5 to a 1983 120hp mercruiser, not exactly sure how much I need to transfer over