Pontoon Boat & Deck Boat Forum

I have a new to me 2009 Bentley 240 Cruise with a 2015 Mercury 115 4 stroke.

It was not propped correctly when I bought it. It had a 21 pitch 3 blade and would turn 4400ish at WOT. Speed was around 18.

I changed to a 3 blade 15 pitch and easily hit 6000 at WOT. Speed is around 26mph. I can easily hit the rev limiter alone and hit it a few times with the wife and kids aboard.

I’m leaning toward moving to a 17 pitch in hopes of not over-reving but still staying in the suggested WOT (5000-6000).

Should I go 4 blade or 3 blade? And am I on target for the pitch? Dealer suggested the prop I have and it’s just not right.

Also, motor is a 20” shaft and plate sits approximately 1/4 inch below transom and can’t be lowered any further.

Thanks for the help!

The next pitch up with the same model of prop will get you their. The problem with trying a 4 blade or even a larger diameter cupped 3 blade of different model is that you will be back to square one in finding the right pitch. What diameter is your current prop?

13.5

I have the same motor on an 18' tri-toon and have a 13.5x17 black max, I hit 5,500 RPM's tops.

I tested the 17 and only hit 5200-5400 depending on water conditions. This was alone with half tank of gas and top down.

I’m still considering trying a 15 pitch 4 blade just to say I did.

I borrowed a 4 blade 15 for a day of tubing, i hit 5800 RPMs and cornered much better, I'm definitely buying one, I've just been to cheap.

Timely thread....I spun the hub on the prop that was on my motor just a couple weeks ago...it was a "Michigan" and the fastest I could ever get it to spin, was 4500. I put a OMC prop on that was supposedly the same pitch and diameter and the rpms went up 1K but speed dropped 4 mph at the same 4500 rpm...I ordered a "turning point" prop with the same pitch and diameter, because I think my motor has a carburetion problem and "turning point" has a "pitch exchange" program...I'll repost the results in a few weeks, after I get my carb boiled and the new prop on....

I have the same 240 Cruise as you with a 115, only in a 2007 version. It came with a 15p 3 blade when I got it new and worked fine on Hartwell. When I got it back to Boone Lake in TN it was a dog. There was close to a 2000 foot difference in elevation... I got a Mercury Nemesis 13.8x13 4 blade and it worked wonders, better hole shot, better cornering, could reach the RPM range required, etc.

Now I'm back down at about 400 foot elevation and will probably get the same prop in a 15 inch. So, there's that additional factor to consider... elevation.