Posts: 1936
Location: Eau Claire, WI | Here's a " for what it's worth".
One of my boats is a welded hull Alumacraft model "Waterfowl 16", I have a 25hp four stroke Yami on the back. Suspect my loaded weight ratio is very similar to yours.
I have a 36 pound transom mount MK 12 volt and a bow mount power drive that is 40lb thrust 12v. Both have more than enough power to move that boat just fine.
Bear in mind I only use this boat fishing small river systems or smaller lakes. It's primary use is for waterfowl hunting and I remove the trolling motors for that purpose. But when I have used it with the trolling motors the lower thrust 12volt work just fine.
Good luck |