Transom Adapter ?

[starsnstripers]

Does anyone know if Iboats or anyone has a transom adapter to swap an OMC to a Mercruiser? I've heard that they are available, i just don't know where or how much? Alot of people are interested in this swap over due to the OMC situation. Thanks

 

[Don S]

Re: Transom Adapter ?

There isn't one to convert a stinger to a Merc 1 drive or newer.
The OMC Cobra doesn't need one. Same hole thru the transom.

 

[oldsub86]

Re: Transom Adapter ?

There was an adapter plate available at one time. I know I read somewhere on the net that the adapter is no longer available. One would have to find a used one - or machine one. Nice big chunk of billet aluminum and a big mill??

Randy

 

[oldsub86]

Re: Transom Adapter ?

http://www.sterndrives.com/omc_to_mercruiser.html

 

[180shabah]

Re: Transom Adapter ?

It would be cheaper to replace the transom and cut a new hole. No billet, no expensive machining equipment, just plywood and fiberglass.

 

[starsnstripers]

Re: Transom Adapter ?

Well, They did sell them but their discontinued. Bummer! Here's some instructions on how to do it though. Ummm Well maybe i shouldn't post it here being it's another Mercruiser parts etc. sight. Dont know the rules on that. Anyway, it says to fill the whole in properly by an experienced fiberglass person. If anybodys looking for that plate.

 

[chiefalen]

Re: Transom Adapter ?

What your talking about is going from a electric shift or stringer 78- 85 unit to a merc setup.

And how that is done is in the thread you posted. You have to fill in the big round hole and and drill with a template the openings for the merc drive.

As long as you have everything for the refit such as inside transom plate bellhousing for the motor and everything else for the merc setup you don't need no adapter plate.

If the omc unit is 87 and up cobra units you need the setup as before everything like the inner transom plate drive and bellhousing for the motor you don't have to fill nothing in cause the cutout is the same. Again no plate is needed.

 

[starsnstripers]

Re: Transom Adapter ?

Whoa! Found it! See attached! And they still sell it

 

[chiefalen]

Re: Transom Adapter ?

Why do you need that? To make up the difference in the thickness, or because your gonna use the inner transom plate from the cobra setup?

 

[starsnstripers]

Re: Transom Adapter ?

Correction > This is an adapter plate to convert Volvo to Mercruiser! Darn

 

[Don S]

Re: Transom Adapter ?

Not only the old Volvos, (270 and 280's only. Not the 290's) but BMW as well. PN is 827691A1 and now costs about $1100.

Cheaper to replace the transom properly and recut the hole.

 

[chiefalen]

Re: Transom Adapter ?

I was gonna hang it up cause i thought i lost my mind.

Volvo not my thing.

And i think some Volvo's you won't need the plate ether cause i think the sx series is the one that is the same as the cobra of the same year.

Now to be clear i said i think and am not absolutely positive.

 

[mthieme]

Re: Transom Adapter ?

Here's my plate. It went from a Stringer to a Cobra in '89.
Pardon the mess, the cleaning lady hasn't come yet this week.

 

[Don S]

Re: Transom Adapter ?

Anyone care to read reply #2 in this thread.

 

[starsnstripers]

Re: Transom Adapter ?

Yes Don, :redface: They did offer one at one time though, correct? Wonder why they discontinued them? The volvo to merc ones are 7-900 bucks. You know how much they could make selling those things? And it's good for Mercruiser. I might need one someday!

 

[Don S]

Re: Transom Adapter ?

Merc never made one to cover the stringers that I know of. Only the one I gave a part number for. Never used it, but it may cover the stringer.
Buy one and let us know, PS. I gave the present price. Not one from years ago.
Another note, the stringers had 2 different mounting heights, trying to make an adapter for both heights would be way more expensive than a new transom. Besides the transom thickness for the stringers was a lot thinner than the Mercs. The stringer drives were supported by the stirngers (kind of explains the name doesn't it), while the Cobra's and Mercruisers had thicker transoms because the support was in the transom and the rear mounts of the engine being on the transom shield.

 

[mthieme]

Re: Transom Adapter ?

SnS - what model OD do you have, or was your question general?
Don is right, you either bolt up a MC to replace a Cobra, or you're redoing the transom. I can't imagine a plate to take up the slack a stringer would leave.
Also, the adapter plate you found, was if for a Volvo SX by chance?

 

[Don S]

Re: Transom Adapter ?

SX is the exact same thing as the Cobra and Mercruiser. (Alpha and Bravo)

 

[starsnstripers]

Re: Transom Adapter ?

Mthieme, It was general toward a stringer adapted to Mercruiser i'm looking at a couple bertrams that had stringers and i'd swap em to Mercruiser. My friend has a stringer and he'd like to convert and oldsub on here posted he'd like to do it. Don, it was said that outdrive.com sold them for awhile but no longer do. Saw it in a post on offshore site. I think it should be able to be done easier than the fill/fiberglass way. I would try this( see attached) Use two fabricated plates of thick aluminum, maybe one can be flush because like you said don the stringer transom was thinner. If you can sandwich the transom with a filler in the middle sandwiched by say 3/8-7/16 Aluminum and cut out the Merc template in it. Seal drill and bolt! Rough drawing but you can get the just. Would cost less than $8-900.00 too

 

[mthieme]

Re: Transom Adapter ?

Ugh. I was never a big fan of stringers to say the least.
You might consider a bigger plate - take another peek at my transom.
Obviously, mine overlaps the original transom considerably. It's all wood and still rock solid.