I think I'm propped right?

brownboat

Cadet
Joined
Jul 11, 2006
Messages
17
Well my classic 1964 runabout finally bit the dust with a blown cylinder. Lucky for me, a neighbor had a seldom used pontoon boat for sale. So now I?m the very happy owner of one and love the versatility and room.
There was no tachometer, only a trim gauge and broken speedo. I felt uncomfortable without a tach so I installed one and I?m wondering if it?s propped correctly.
It?s a 25 foot Premier, 25 inch tubes, with a ?98 Honda 90hp four stroke. It came with two props. The spare, which I think is the original, is a SS 13 3/8 x 14P. The prop on the boat is a Turning Point Express SS 13 ? x 15P. With me, wife, and daughter on board WOT is 5500. With a load of 8 people and a big cooler WOT is 5200.

The range according to the Honda manual is 5000-6000, so I think I?m propped ok but was wondering what the wisdom of this group thinks. I was also wondering what a good cruise RPM would be. At about 3300 the boat feels like it sits up and the bow comes down, similar to what it felt like when the old boat would come up on plane. Thanks, and sorry if this should be in the props topics forum.
 

EGlideRider

Lieutenant Junior Grade
Joined
Dec 14, 2008
Messages
1,000
Re: I think I'm propped right?

You are propped perfect and your cruising RPM of about 3500 is also great. You indicated a 'seat-of-the-pants' feel at 3300 and that is always a good judge of performance.
 

The Rooster

Ensign
Joined
Apr 28, 2011
Messages
936
Re: I think I'm propped right?

Hey "brownboat" if you think you will be carrying a heavy load of people and gear often, ie, 50% of the time or more, you might consider the smaller prop. 5200 rpm, WOT might be lugging the engine somewhat. You should be in the sweet spot, efficiency wise, between 3000-4500 rpm cruise.
 

brownboat

Cadet
Joined
Jul 11, 2006
Messages
17
Re: I think I'm propped right?

Thanks EGlideRider and Rooster, I was hoping the 15 pitch would be OK. The spare prop is a little banged up, that's why I didn't want to try it out. Think I'll get it fixed and consider putting it on if I have a full load most of the time. The pontoon boat seems to draw a crowd :)

Now it's off to the iboats store to buy some hardware.
Thanks Again
 
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