heavy-chevy
Well-known member
i have a 20" shaft and i have read on another forum that the cavitation plate should sit level with the bottom on a john boat, so i built my transom according to this. last time i ran the boat i looked back for the first time at the engine and noticed that the bottom fin runs under the waterline and about an inch or two above it is dragging. now i have read that on a normal boat it should be 1-1.5 inches above the bottom of the boat. i know on any other boat that plate runs above the water line, but i have no previous experience with john boats. so my question is, is a john boat supposed to run this way or do i need to move the engine up more. it runs fine this way, but i was thinking maybe i could pick up a little more speed/fuel mileage.