Placement of '83 Evinrude 35 on 1990 Duracraft transom

[surfshark]

This may seem like a dumb question...I'm putting a 1983 long shaft Evinrude 35hp on my 1990 Duracraft jon boat. I understand that I should center the motor on the transom and that the cavitation plate should pretty much be within 1 inch of the bottom of the boat. Here's my question: what do you call the long rib-like things that run the length of the boat on the bottom? Do I line the cavitation plate with the flat part of the bottom or the closest rib that extend about an inch further? The midline point of the bottom is centered between the 2 center "ribs". Thanks for any help.

 

[Daviet]

Re: Placement of '83 Evinrude 35 on 1990 Duracraft transom

Cavation plate should be even with the bottom of the boat. Never had a jon boat, but on a boat with just one rib, it is called the keel.

 

[Cofe]

Re: Placement of '83 Evinrude 35 on 1990 Duracraft transom

I have the same boat with a 1990 evinrude 25 short shaft on it. The cavitation plate runs just perfect in the water......just at the surface of the water at WOT.

You will just have to test your's out to see where the cavitation plate runs at. And those ribs on the bottom are just for rough abuse on rocks,,,,dragging...ect.