Convert a sterndrive to outboard?

alk

alk

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Anyone familiar with converting an i/o boat to outboard? when I was sitting in my bilge in the midst of a shift cable replacement project last saturday morning, because it’s getting close to impossible to find any mechanics able and willing to work on a stern drive around here, I got to thinking about it.

I’ve seen a bunch of YouTube’s doing exactly this, and the boatyard I’m at has experience with this project. probably cheaper to just sell my boat, and buy something designed for an outboard. But I sort of like the idea of converting. boat is a 1999 23’ Wellcraft Excalibur bowrider - sort of looks like a Baja of the late 90’s vintage. Runs with a 310 Hp 454.
 
Perhaps consider a bracket for the outboard. Should be fairly easy.
 
psalzer said:
Perhaps consider a bracket for the outboard. Should be fairly easy.
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That's likely the easy part; there's that massive hole in the transom you'll need to securely fill.
 
Filing is pretty easy with Coosa and glass on both side. Probably a worthwhile project if you like the boat. There a different bracket that can be used
 
I'd be concerned whether or not the transom can handle the thrust of an OB and not flex. Then again the outdrive does something similar although its bolted to the engine which is bolted to the stringers. Hmmm....tread carefully but you might be better off finding the right boat.

A friend has a 23' Proline with I think a 225hp on a bracket. I don't know if the bracket helps with geometry but his boat JUMPS out of the water and is PDQ.

I'm at the point where climbing in and out of the bilge is not as much fun as it used to be. I love staring at the outboard of my center console when it is out of the water, much easier to work on.
 
i think my biggest problem is that my transom isn’t flat - molded in swim platform. So won’t be as simple as The YouTube’s I’ve watched, where they pretty much patch the hole, thicken the entire transom, and add some bracing from the transom to the stringers, and bolt a bracket on. Mine would require some work to the platform. The yard I’m at said ‘it wont be that bad’, but not sure what that means in terms of dollars. They have some expert shipbuilders; people bring their boats from all over to have them extended, and all other types of structural work - so i assume they know what they are talking about. my preference would be to buy a center console, t-top, with an outboard. But holy cow, those are expensive these days ! Like 50 grand for a used 23 -25 footer in decent shape.
 
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Your link is bad but I found pictures of others. I don’t think it’s going to work as the transom is pretty low above the water and moving the engine weight further aft, behind the transom isn’t going to help either.
 
From my totally not knowledgeable perspective that looks like a bunch of work to get it looking and performing right. However that said, new boats are crazy expensive. I would get a formal quote and a artist's rendering of what the boat would look like after completed. For example I can envision a setup with the outboard/ outboards set inside a cut out swim platform with the new plarform just being a boarding ladder on one side and using the other for your transducer.
 
I should probably just lose some weight, and take up yoga or something - so i can contort my body into this bilge for a few more years. Parts are still easy enough to find - especially since I yanked the mpi, computers, etc. Just a bummer that no one wants to work on them anymore.
 
I feel your pain. I've consider the same thing on our Luhrs 290 with the twin Yanmars. While I know it's doable (the factory made one for a VP when he retired), the amount of work involved in a conversion would extremely pricey.
 
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Wait, how hard can this be? That guy on TV makes a whole boat with just that Flex stuff.🤪🤪🤪🤪🤪
 
I would just buy a few more service manuals and a Dicom to read all the ECM codes if needed.
 
ddurand said:
I would just buy a few more service manuals and a Dicom to read all the ECM codes if needed.
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There are no more ecm codes - after the only shop around here that was willing to work on these motors could not diagnose my idling problem last summer ( wasn’t throwing any codes, just would not idle at steady rpm) - I tore out the mpi, ecm, everything, and went with an edlebrock carb, and a simple ignition. Perhaps an overreaction on my part, but runs great now. However, looking to the future, it is hard to conclude we are not nearing end of road for outdrives.

I will perhaps always be able to get the motor to run, although chevy stopped making 454’s over twenty years ago, so another dead end product. But the drive itself is going to be a problem, as they don’t last forever. Replacement parts, and people who know how to repair or rebuild these drives, are disappearing by the day it seems. I couldn’t even find anyone willing to install a new shift cable, which is about as simple as it gets. Outboards are the future, only question is if I make the move to a different boat, convert this boat ( unlikely), or retire from boating. I don’t see myself changing shift cables 15 or 20 years from now!
 
Visit A performance boat shop that has an offshore racing team. They would have done it many times.
 
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