Re: The evinrude 9.9/10hp carb change to make it a 15hp urban legend.

[Alan]

I did this swap, and was very happy with the results!

Mine is the earlier style, which does not use the tuned exhaust, and I did not get into the reed valves; just a carb swap.

I don’t bet that I’m getting a full 15.0 horsepower out of it, but it’s a lot stronger, and pushes our 19′ aluminum boat quite well. It even got me home, (several miles in rough seas), when the main motor quit. A windy day, with four adults on board, and we motored back quite nicely.

Happy motoring!
Alan