90hp prop size

[Lonnie5]

Have a 24ft. Pontoon with a 90hp evinrude need a prop size starting point thanks.

 

[Bob_VT]

Need a bit more information...... is there a prop on it now? Do you have a tach? What motor is it. Toons are hard to push so a 15" pitch would be a "general" good starting point.

 

[Blackhawkdriver]

I would truly be interested in this. Just before my motor died I went with a four blade 13 in with 13 pitch it seemed to work really well. For the thirty plus minutes I got to try it out. Doesn't seem to work in reverse so well but that what I've here about four props

 

[rogerwa]

I would start with an 11P prop. I have had a 25' with a 90hp and I used an 11P. I would have a number of people on board usually so I targeted that load to have my RPM in range. I now have a new 25' with 25" toons and a 115hp 2-stroke and I use an 13P pontoon prop.

You want your RPM WOT in the upper recommended range with the normal load.

 

[BigDfromTN]

Im running a 13P 4 blade. Quite happy with it.
I get 20 +/- mph (depending on load) on our 24' with 90 Mercury 4stroke.

As for reverse... I have heard that a 4 blade helps in reverse versus a 3 blade. We "beach" our pontoon on sandy river banks regular and have not had any problem powering up or off the beach.

Check your current prop size and RPM at WOT. Go from there. Most pontoons run from 11-15" pitch.

 

[Mi duckdown]

What Bob VT posted. Those other post Mean nothing.

 

[rogerwa]

What Bob VT posted. Those other post Mean nothing.

The master has spoken. I regret sharing my 10+ years of experience with multiple boat, engine, prop combinations that seem to be in the sweet spot of what the OP was asking about. Next time I will remember your wise contribution.

 

[ahicks]

Roger, don't be too thin skinned about comments you see in places like this. It's a collection of personalities, and people don't always agree on everything even if the "right" answer is apparent. If we all agreed on everything, it would be a pretty boring place? This is from a different forum, but I think it suits our purposes well?

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