replacing an OMC seadrive with an outboard... set-up questions

[3car]

Ok, heres the deal. I have a 19' sportcraft cuddy that came to me powered by an OMC 1.6 seadrive, which just dosent excite me. I decided to repower and picked up a 2 stroke suzuki 175 with a 25" shaft. After some thought and research, I decided to cut the transom for a conventional type mount instead of buying a bracket, mostly for economical reasons. now, my question is how do I find the correct height to mount the engine?

 

[WillyBWright]

Re: replacing an OMC seadrive with an outboard... set-up questions

Transoms are typically at a 10 to 15 degree angle from perpindicular to the keel, so 100 to 115 degrees. But transoms that SeaDrives mount on are typically perpindicular to the keel, or 90 degrees. That might be a problem. Outboards need that extra angle. The 25" height is figuring a perpindicular line from the top to the the keel. On angled transoms, the measurement from top to bottom of the transom is about 26".

Actually you measure to the bottom of the hull and ignore any keel that sticks below it.

I hope that isn't too confusing. A picture is much easier to understand. Hopefully somebody's computer is better equipped to provide that than mine.

 

[tashasdaddy]

Re: replacing an OMC seadrive with an outboard... set-up questions

there is a great diagram on the forum, but i can't find it.

 

[3car]

Re: replacing an OMC seadrive with an outboard... set-up questions

there is a great diagram on the forum, but i can't find it.

someone please help!

btw, my transom is 12 degrees.

 

[tashasdaddy]

Re: replacing an OMC seadrive with an outboard... set-up questions

if you extend the line of the keel of the boat out, the AV plate should ride 1" higher. than the line and be in horizonal to the line. this is extremely crude, i'm not artist.

 

[Solittle]

Re: replacing an OMC seadrive with an outboard... set-up questions

If you were on the south east coast I might want some info on the SeaDrive. I have a pair of 1987s & kinda would like to repower - - or have a spare sitting ready to go along side the house.

 

[phatmanmike]

Re: replacing an OMC seadrive with an outboard... set-up questions

do it the right way, the first time. buy the bracket.

the resale of a boat that HAD a full transom and was cut down into a notched transom, is a deal breaker.

BUT... if you have a 25 inch shaft motor, measure up from the bottom of the pad( sport crafts have pads instead of V's) , measure up 25 " . yes , its just that simple.

 

[Frank Acampora]

Re: replacing an OMC seadrive with an outboard... set-up questions

Just a thought before you cut that transom!

Most people don't realize it but the built in motor well on a factory built outboard boat is designed to help support the transom against engine loads. Go look at an outboard and see how loads are transferred through the transom into the well and then into the hull. The transom is not a stand alone piece on any boat carrying an engine.

Once you start cutting into a boat without a well, you are compromising transom integrity. If you can't afford an aftermarket bracket, fabricate your own out of heavy duty aluminum, plywood, and fiberglass. It will probably cost the same as cutting and re-glassing the existing transom and probably take less time. Plus--since it will be off the boat, it will be MUCH easier to work on.