06-06-2008, 07:27 PM
Not quite sure what type of boat expert you are looking for but your measurements and estimates sound funny.
The motor is either a short or long shaft. When measured properly, the short shafts are 15"-17" inches, and long shafts are 20"-22" inches. There are a few models with 25" inch shafts but that is of no concern to you.
I don't quite picture how you measured your outboard shaft length. Here is a link to a picture that does a good job of showing this measurement correctly.
[url "http://www.onlineoutboards.com/article_outboard_shaft_length.html"]http://www.onlineoutboards.com/article_outboard_shaft_length.html[/url]
If you measured yours the same way, and got 17 inches it is a short shaft.
Putting it on a 20" Transom is a very bad idea. It is a good way to put a motor to waste. The prop should be completely below the transom, otherwise it will not be balanced, even at low speeds. When it picks up speed it will not be able to suck up water for cooling. And how would you adjust the trim angle when you don't have enough length to work with. What's worse, your manuverability will suffer big time.
If you get into rough water with the 20" transom boat and the motor is running it will get real ugly. You will have no manuverability whatsoever.
It would be a shame to ruin a motor even if it is old and you are planning to get rid of it. Just about the only thing you will be able to do for the sake of saving the motor is going very slow, and always watching the water contact. That sure ain't no fun. It is possible to pull this off but I would never do it.
[signature]
The motor is either a short or long shaft. When measured properly, the short shafts are 15"-17" inches, and long shafts are 20"-22" inches. There are a few models with 25" inch shafts but that is of no concern to you.
I don't quite picture how you measured your outboard shaft length. Here is a link to a picture that does a good job of showing this measurement correctly.
[url "http://www.onlineoutboards.com/article_outboard_shaft_length.html"]http://www.onlineoutboards.com/article_outboard_shaft_length.html[/url]
If you measured yours the same way, and got 17 inches it is a short shaft.
Putting it on a 20" Transom is a very bad idea. It is a good way to put a motor to waste. The prop should be completely below the transom, otherwise it will not be balanced, even at low speeds. When it picks up speed it will not be able to suck up water for cooling. And how would you adjust the trim angle when you don't have enough length to work with. What's worse, your manuverability will suffer big time.
If you get into rough water with the 20" transom boat and the motor is running it will get real ugly. You will have no manuverability whatsoever.
It would be a shame to ruin a motor even if it is old and you are planning to get rid of it. Just about the only thing you will be able to do for the sake of saving the motor is going very slow, and always watching the water contact. That sure ain't no fun. It is possible to pull this off but I would never do it.
[signature]