Pontoon speed right ?

SkiDad

Lieutenant Commander
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Jul 18, 2010
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1,518
Hi All, familar with outboards but haven't been on a pontoon. Our neighbors took us out today. 22' pontoon with a 60 hp Mercury Bigfoot. With 7 people weighing 1200 lbs it topped out at 12 mph. I watched the RPM and it was at 4400-4800. I checked the prop and it was a 14x11 - which seems right to me. The engine ran very smooth, It just didn't seem like the engine was opening up.

the prop has some damage but it wasn't excessive. Would this be a normal result with this many people? . I was thinking a 60 would push a pontoon about 20 mph and turn more like 5500 rpm

PS - forgot to add the poontoons were very slimy
 
Last edited:

bruceb58

Supreme Mariner
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Mar 5, 2006
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30,454
Probably about right if the pontoons had a lot of growth on them. The pontoon in my sig has that size prop and at around 5000 I go around 16 loaded down. Mine is at 6800 feet elevation. At sea level I use a 14x13 and I can go over 20 .

If a prop has ANY damage, it should be repaired as it can affect top speed as well as damage the lower drive unit.
 

wahlejim

Master Chief Petty Officer
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Jul 23, 2015
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That is a heavy load and big boat for that motor. It seems right to me. I have a 25 foot toon with a 50 merc on it. By myself, I go 18, loaded with people I am at 12-13.

Also, my speedo is inaccurate. It says I am going 14 when gps is at 18. Likewise, the needle barely moves (speedo starts at 10) when loaded and my gps says 13.
 

jkust

Rear Admiral
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Aug 2, 2008
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4,942
That sounds about right to me based upon the million or so pontoons on my lake. Good friend of mine on the lake has a similar sounding pontoon with a 150 and gets 21mph. Don't know which prop he has however.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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'toons are not for speed....they are a platform to fish/drink/grill/golf from
 

ahicks

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Sep 16, 2013
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It's kinda like a ski boat when picking a prop. The "right" prop is going to depend on a few factors, including how it's normally loaded. With the pontoon, the issue is if you want to prop it for 7 people on board, a more typical load, or lightly loaded with just one person on board. The problem is, if it's set up for a heavy load, then operated at WOT with just one on board, you're going to have to be careful not to over rev.

And as you can see a 50-60 hp 'toon will run in the teens. Where, will depend on the load.

Last, you don't say if the Big Foot is 2 or 4 stroke. If it's a 4, they get to sounding pretty busy when run at max rpm. I've found they sound much better, and perform just as well, when run about 500 rpm below max.
 

Sea Rider

Supreme Mariner
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Sep 20, 2008
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12,345
If your neighbor will be boating frequently with 7 up, need to prop engine right to rev at least middle to max wot rpm range factory stated, will perform much better as from know which seems is running at the lugging side ? just don't expect to be a speed demon. Varying loads can kill any well propped engine, worse if being under powered.

Happy Boating
 

SkiDad

Lieutenant Commander
Joined
Jul 18, 2010
Messages
1,518
thank you all for the responses. The guy is my retired neighbor. The boat weighs 1800 lbs and i figure the motor, gas and gear are another 500. He had hopes of tubing it but 11 mph on a tube is just for little kiddos. I'm not sure if cleaning it up and a new prop will pick up 5 mph or not ? I think it will generally be more like 5 people - we were just there to show them how to hook up the tow bridle and check it out.

the pontoon is a 2006 Sunchaser 22' and the motor is a 2006 Mercury 4 stroke - 60hp. The prop is a Mercury black max 14x11 but not a pontoon version.
 
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