mercruiser 120 omc mercruiser 5.7 transom cutouts

[digitalman]

when repowering a boat that had an omc cobra with 5.7 gm. are transom cutouts same for mercruiser as omc and for that matter are the cutouts for mercruiser 120hp same as the mercruiser that has the 5.7 gm v8?

What options are there? possible?

 

[Don S]

Re: mercruiser 120 omc mercruiser 5.7 transom cutouts

The cutout for the OMC Cobra is exactly the same as the Mercruiser.
The cutout is also the same as the SX and DPS drives Volvo now uses.

 

[Bondo]

Re: mercruiser 120 omc mercruiser 5.7 transom cutouts

Most of the Mercruiser Cut Outs are the Same,.......
Alpha Gen.II,+ the Bravo have 2 extra Bolt Holes.........
Earlier Alphas,+ Pre-Alphas are the Same......

I've heard that the Cobra cut Out is the same as the Merc.'s but Don't know that for a Fact........

 

[achris]

Re: mercruiser 120 omc mercruiser 5.7 transom cutouts

The cutout for the really early Mercruisers (pre 1974) is slightly narrower in some parts than the later ones, and 2 of the bolt holes have to be moved up about an inch.

Chris (CI)...............

 

[digitalman]

Re: mercruiser 120 omc mercruiser 5.7 transom cutouts

so it would be possible to put a 4 cyl 120hp mercruiser in a boat that had a 0mc cobra with 5.7 gm? If what I wanted was a economical but slow cruiser? Or is only option 5.7 mercruiser? Could I put a volvo diesel unit in?

 

[Don S]

Re: mercruiser 120 omc mercruiser 5.7 transom cutouts

What year engine and drive do you want to install in that Cobra hole.

Could I put a volvo diesel unit in?

Which Volvo diesel Unit?????
There are LOTS of different ones.

 

[Bondo]

Re: mercruiser 120 omc mercruiser 5.7 transom cutouts

You can put about Any motor in about Any boat,..............

All it takes is Time, Effort,+ Money...................

 

[Don S]

Re: mercruiser 120 omc mercruiser 5.7 transom cutouts

Chris (CI)...............

I luv it

 

[digitalman]

Re: mercruiser 120 omc mercruiser 5.7 transom cutouts

well as far as the volvo's..which ones would work? old stern drive 1987 omc cobra with 5.7liter gm. I would assume the normal things..differrent motor mounts and such...that would be same for the 4 cyl 120hp mercruiser in the omc cobra hole?

Anybody doing anything else when repowering to save on fuel costs? If I have to repower anyhow..why wouldnt I want that? I dont mind reduced speeds etc..fair weather boater close to shore and ICW mostly.

Thoughts? And thanks for knowledge transfer!

 

[digitalman]

Re: mercruiser 120 omc mercruiser 5.7 transom cutouts

my thoughts on which to replace would be the 120 hp mercruiser would most likely be the easiest. Volvo diesel would be the preferred. As to which year etc..I would hunt up a unit for the best year...ie at least with electronic ignition etc.

Thats all a guess tho that the 120 mercruiser would work. Probably the easiest and least expensive to buy..I figured to find a boat with appropriate stern unit and strip it...there are alot of freshwater ones aroud where I live.

 

[digitalman]

Re: mercruiser 120 omc mercruiser 5.7 transom cutouts

after looking at this forum about stern drives..sounds like if gas then the 3.0 mercruiser would be a good option for repowering from the OMC cobra,,,and if I could get some help on which volvo diesels would work..since there seem to be alot of them...I would appreciate any expert opinions.