prop pitch for 15hp Johnson

[woodsdweller]

My 15hp Johnson used to push my 15' boat around 16-17 mph, just right for small lake fishing. When I started her up this spring I lost about 3 mph for some reason. Then I hit a rock reef (going pretty slow) which dented the prop. Prop was the original 1985 three blade 9.5"Dia. x 10" pitch. Took it to the shop and they said replace it. They had a 9 pitch four blade power prop in stock which they recommended. I went with it and have to say I almost think its even slower on the high end, minus the vibration my damaged prop gave. I guess I expected to return to my 16-17 mph of last fall.

What is the proper prop for this motor? Should I return this new one? Any thoughts as to why I have lost speed over the winter? How would I tell if I damaged my lower unit scraping those rocks?

Thanks, Woodsdweller

[woodsdweller]

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