Pontoon Prop Question

[mikenky23]

I have a 24' Bentley pontoon powered by a Mercury 115 4 stroke with a 14x11P prop. My pontoon runs about 25 mph at WOT with 5100 rpm. Can anyone recommend a prop that might improve performance? I was looking at Mercury's 4 bladed prop for pontoons and they recommend a 13.8x9P. Has anyone tried this new prop? Looking for suggestions.

Thanks,

 

[steelespike]

Re: Pontoon Prop Question

Pontoon speeds are all over the place.
I wonder if your rpm is in error I checked several Merc. tests most were 11" pitch and running 6100 to 6400 rpm and running 22 to 24 mph. Its seems your right on except for the 5100 rpm.
If you go to the 9" prop you will lose speed.

 

[msbrown]

Re: Pontoon Prop Question

I have a 21 Southland pontoon1999 . I am putting a 2011 75 hp Merc 4 stroke. WOuld a 13 3/4 x 15 be good? What would a 13 1/2 be different. We want to run along a mid speed not for speed. Only when a storm is coming a long. Thasnks for any help.

 

[mikenky23]

Re: Pontoon Prop Question

I put a new tach on and used my GPS, here's what I came up with. 5400 RPM and 22 MPH with a 14x11P prop. I rechecked the numbers on the prop and they are right.

 

[steelespike]

Re: Pontoon Prop Question

Again, except for your rpm your right on line with the outfits I checked.
It would appear that either the motor is a little weak or perhaps setup too low or too high.
Is your prop stainless?Perhaps boat needs to be balanced differently.
If the prop is cupped you might be able to have some cup removed I've seen this raise rpm and speed.
Is there any water in the logs?Does it seem to sit extra low at rest.
If you add a water glide ,I think its called,like a third log. The boat will run all most like a runabout.
Also you could skin the bottom for more speed.