1955 25 hp Johnson prop question

[R. Bushie]

What would be a better prop selection for my 16' cedar strip boat powered by a 1955 25 hp Johnson RDE 17. When I first set this combo up I used it as a tiller arrangement ( seated aft) and have since equipped it with remote control and steering where I'm sitting in the midship position and the boat's top end speed is a bit slower with this set up. At present the engine is equipped with a 10.5 X 12 prop. The boat with motor, equipment and one person the total weight is about 800 lbs. Even though this combo works okay is this prop the best for this weight/boat/motor combination and if another 150 lb person is carried will this make a difference?

 

[Paul Moir]

Re: 1955 25 hp Johnson prop question

I would think that that prop is just about right for your rig, but the only way to tell for sure is by knowing the WOT RPMS of the engine. The least expensive way to find that out is with a TinyTach. Unless you have a clip on diagnotic tach handy.<br />That engine has a very long leg, so there's lots to be gained by raising it on the transom. Just make sure each time you raise it that you're still getting water out the back at idle and WOT.

 

[Chinewalker]

Re: 1955 25 hp Johnson prop question

Also, with your movement of weight forward, you may benefit from having the motor kicked out one notch on the tilt adjustment.<br />- Scott