Am looking at gettring a Zodiac for family play and diving. Looking at Mark IIs which call for a short shaft motor. But I already have an older 18 horse long shaft.

Would I damage the boat using a long shaft? What about building up the transom a couple inches?

Thanks for a inflatable novice.
Eric

Hi, your suggested solution is not one to be recommended, and many would say that it is definitely a bad idea. The relationship of the engine torque and the boats centre of gravity will be mismatched.
Building up the transom is not a good idea either.
Best to look for a boat / engine that are compatible.
cheers

bad idea. with such a long shaft, the boat will drag and planing will be next to nothing. the transom may not be able to handle the extra weight and you run the risk of transom seam damage. I agree, match up the correct size boat with your engine.