Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Prop advice for a 90 yamaha two stroke on an 1988 montauk

Posted by jaxmyth on 08/11/15 - 10:42 AM
#39

well, I decided to try the old prop from my 70hp on the 90hp motor and there was a noticeable difference in rpms. the prop that was on my 70hp is a 13x17 prop also. I believe it was a Yamaha prop because it has 13X17K stamped on it. is this indicative of a Yamaha prop? with the old prop my rpms went up to 5k and the top speed was 38 mph at wot. I had a decent load in the boat and 20 gallons of fuel.