Repowering 20' AS question.

[ralpht44]

I currently have an 84 200 Horse evinrude. I have decided to repower with a new/er Evinrude or Johnson. My current motor is a 20 inch shaft. Can I put a 25 inch on this boat without an adverse effect? I would think I can but want the experts take on this.

[GoneFission]

If you have a 20 inch transom, you would need to use a bracket to lift a 25 inch motor to the right height.  This also adds addition moment and stress to the transom, so be sure your transom is solid.  Putting a 25 inch motor on top of a 20 inch transom means either the prop is 5" too low, or the top bolts on the motor will not be in the transom - either is a bad idea!   :cry:

If your transom is solid, you would probably like going to a 25 inch, as it keeps the motor out of the water more.  If you want to spend the bucks for a power bracket, it also makes the boat more flexible for shallow running...

[fnichols]

Check out the 25" transom-mistake posting about 6 messages below your posting.  There is good info. in that posting about 20" vs. 25" motors and jack plates.

[ddd222]

switching shaft sizes is something i've heard for some reason this year way more than others. As far as i know there are 3 options, bracket, jack plate, or building up your transom a few inches. The last option being the best from what i've heard but only if done right. Is weight of new motor different?(keep in mind jack plate or bracket you'll need a few extra feet of control cables.) Quickest, least expensive option in my mind would be the jack plates, recently had a buddy w/ old grady he put a jack plate and a good used yamaha 200 on, very happy to date. Bracket comes w/ performance issues on smaller boats(much info on classicmako.com), in some cases i've read to very unacceptable levels. Most around performance an attitude. Engine weight now further back than designed causing porpoising and listing and different planing characteristics, some at mako correctable, some scrapped completely.
   Hope helpful