Re: Prop size and pitch for Carolina Skiff J16CC and Yamaha 40hp 4 cycle
The total weight of the boat will be the end factor in determining what prop you eventually end up with. My J16 is like yours, plus 2 batteries and a trolling motor. By myself, I use a 11.6x13 prop and turn about 5300rpm. If I have someone else aboard, I switch to a 11.6x11 to keep the rpm's in the 5500-5700 rpm. Each inch of pitch change will change your rpm's about 200. The larger the pitch, the lower the rpm's. I would recommend beginning with the 11.6x13
If you have the original Yamaha prop on your motor, to see what size it is, you have to remove the prop and look for the numbers stamped on the back side of the hub edge.
Gary