Short shaft vs. Long Shaft

[surfkruzer]

What are the possible consequences of using a 20" shaft outboard on a boat that originally was designed for a short shaft? Too much torque on the transom? Poor performance? I'm weighing the options of re-building the transom. Thanks for any input!

 

[Bear]

Re: Short shaft vs. Long Shaft

The easiest way is to change your outboard. How much that costs is up to you.<br />You get get better fueleconomy more speed and less risk to hit a hard object below you.<br />The torque on the transom is no problem now. After you rebuilt it, who knows ;-)<br /><br />If you really want to keep both boat and outboard, build it strong.

 

[Dhadley]

Re: Short shaft vs. Long Shaft

You didn't say how big of a motor and what kind boat. It's possible in some situations to use a manual jack plate to raise the outboard to the desired height. Good luck!

 

[surfkruzer]

Re: Short shaft vs. Long Shaft

Thanks Dhadley-<br /><br />It's a 1957 Trojan that originally had twin 35hp Evinrude outboards. I sitll have them, but they are in need of major rebuilding. I'm replacing them with a single 60HP that is a few years newer so I can use the boat. I'm playing with the idea of adding 5" to the transom, but hate to do anything permanent in case I ever get the originals fixed up.<br /><br />Thanks!

 

[Dhadley]

Re: Short shaft vs. Long Shaft

A manual jack plate will work just fine. And it's the easiest solution too. Most have between 5 and 6 inches of vertical adjustment. Most outboards have several mounting holes to achieve additional height. I prefer the ones from Bob's Machine but there are lots of good ones on the market. With the Bob's you can change the set back from 5 to 3 inches and change the trim angle also. Good luck!