Prop question?

Bubbco

Recruit
Joined
Feb 21, 2002
Messages
2
Prop question?

I have just restored a 24' pontoon boat and powered it with a 115 Johnson off a 17' Trihull.The prop on the motor was 17 probably too much prop for such a boat. Does anyone know the average prop size for this type off boat and motor combination?
 

MGuckin

Senior Chief Petty Officer
Joined
Jun 10, 2001
Messages
760
Re: Prop question?

Re: Prop question?

Not sure of this type of hull but why don't you try it. If you have a tach, rpm should be from 4500-5500, I believe @ WOT. Sounds like a good starting size. I think you may have to go a few inches smaller in pitch. 1" of pitch = 200 rpms. Lower pitch will increase rpm. You don't want to lug the motor nor over-rev.
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Prop question?

Re: Prop question?

Absolutly try it and check out the RPM's. It may be a tad stiff. You may end up with a 15 but try what you have. Shoot for 5600 to 5800 RPM with an average load.<br /><br />Good luck!
 

Ross J

Lieutenant Junior Grade
Joined
Nov 30, 2001
Messages
1,119
Re: Prop question?

Re: Prop question?

The book specifics for 115hp Johnson say...<br /><br />Prop supplied with motor - 3 blade, 13" dia, x 19" pitch<br /><br />Ross
 
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