Question from out in left field. PROPELLERS

[Jack]

I’ve propped drag boats and pleasure boats with some success. BUT, my 18 ft. pontoon boat with a 40 HP. outboard is driving me nuts. Blow out, cavitation, call it what you like, the prop breaks lose. I can’t corner or trim up at all without the prop breaking loose. Props I’ve tried, 3 and 4 blade. Pitch 10 to 12 in. diameter 10.5 up to 11 in. My next step is to increase the prop diameter as much as possible, 11.75 to 12.5 dia. X 10 P. and see what happens. What do you think? Speed is not important.

[XstreamVking]

Cup is your friend when messing with tooner. Take a wheel to a prop guy and say, 2x cup please.

[nelson edens]

motor too high

[FMP]

Call PropCo in GA, he has some good props for pontoons.

[RIVERRUMMER 70]

Big dia, cup, stainless, 4-blade or a 60 hp bigfoot merc. call it a day.
we tried setback before and help some but not cure all.... big issue is large dia tubes and light motor.
motor down on transom? i assume 20" motor? yeah it may never work perfect not much you can do ....everyone sit in back or heavy peeps in back, kids in front. idk.
rented a tooner in naples was 18' with a 60 merc bigfoot and stainless vengeance 3 blade, was awesome in the back waters, we flew up to ft meyers and back ran perfect....i was impressed. hope this helps.

[Jack]

Thanks guys.

[Jack]

Call PropCo in GA, he has some good props for pontoons.

Spent some time on the phone with PorpCo. Received the recommended prop today. Now I need the ice and snow to clear so I can try it. Thanks FMP

[FMP]

Hope it helps

[Gordon02]

+1 for the Bigfoot.

I ordered my new Bentley 20' pontoon with a Mercury 60 horse Bigfoot outboard and we loved it. As stated above, the large diameter of the props designed for that gearcase pushed that boat very well in all conditions. Small props don't have the developed blade area needed to push and hold it's bite. I don't believe more cup will help because you're not fighting typical prop slip - it's cavitating and more diameter is what you need. Getting more of the gearcase in the water might help - especially if you've got any blades of the already small prop out of the water at speed. Good luck with getting this sorted.

[Jack]

Thanks Gordon02. The engine is as low as it can go. The gear case can only swing a 12 in. Dia. prop. I don't know where PropCo gets his props, but the prop he sent is a 12 in. dia. 10p. the blades are huge with the tips cupped. We will see.

[XstreamVking]

Sailboat prop maybe.....

[Jack]

Spent some time on the phone with PorpCo. Received the recommended prop today. Now I need the ice and snow to clear so I can try it. Thanks FMP

Huge improvement in performance (remember its a pontoon). BIG ear three blade, with a healthy cup that runs up around the blade tips. Good job PropCo Propellers