Is it possible to install air valves to my logs?

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Silver Eagle

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Funny to read all this....I have actually taken classes in marine engineering and these types of questions come up more than you would think....they are kind of fun.

One rule to keep in mind...when something floats, the amount of water that is displaced, is equal to the weight of the boat. Simple concept.

I assume the positive pressure needed on pontoons is simply to keep them from crushing. Replacing one gas with another will add or detract weight, but doubt its of any measurable difference.

Balloons with helium float because the combination of the helium and the balloon is lighter than air (which is 80% nitrogen and 20% O2 mostly). No amount of light air in a metal pontoon be be of any consequence and the point about the foam above, is spot on....never understood that one...why anyone would fill a pontoon with foam, other than for shape support, is beyond me. It wont float better.

This question reminds me of the Nitrogen scam that tire installers used to sell. When getting new tires, they would actually sell people on the advantage of adding nitrogen to their tires instead of "normal" air and claiming all sorts of benefits. The charge? 10 to 20 bucks. Dumb.

With standard air being 80% nitrogen already, there is no real benefit of going to 100%. Having "dry" air is more of a concern.

​If what you say about putting nitrogen in car tires is a scam then why do the Nascar tires have it in them.
 

bruceb58

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​If what you say about putting nitrogen in car tires is a scam then why do the Nascar tires have it in them.
Its a moisture issue and really has no reason other than that. Same reason airplanes use nitrogen...it's a moisture issue. The benefit for auto tires is negligible hence its just a marketing ploy.
 
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wrvond

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​If what you say about putting nitrogen in car tires is a scam then why do the Nascar tires have it in them.

Nitrogen pressure is more consistent than normal air pressure, because air typically contains varying amounts of moisture due to changes in relative humidity. Water causes air to be inconsistent in its rate of expansion and contraction. Your average grocery getter doesn't perform at nearly the same level as a race car.
 

Buster_boy

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My motivation was to get it to sit level in the water. If you look at the links someone else posted here you'll see what I mean. The first thing to go will be the half-toon in the center of my boat. The second will be the 40hp Johnson.

I'm probably going to trade it in next spring on a 2017 Sweetwater 1680C pontoon, so all of this won't matter now anyway.
 

bruceb58

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My pontoon doesn't come close to sitting level in the water and it really doesn't matter.
 

Buster_boy

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That's great but it bothers me. Mine does nothing but plow and with a 9.9 it goes a whopping 5 mph. Other boats sit perfectly level and fly past me and they've got 9.9's as well.
 

bruceb58

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Do your pontoons have water in them? Have a picture of how it sits?

How long is this boat?
 

MH Hawker

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i happen to run a 9,9 and id its propped right and the load is shifted around a bit you can hit 10 to 12 mph
 

Buster_boy

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16ft Sylvan, no water in logs. 10x9 prop on the Mercury. I don't use the Johnson on this body of water.

fetch


Also has 1/2 log in front which doesn't help. That's coming out next spring.
http://forums.iboats.com/filedata/fetch?id=10269337&d=1464915780
 

bruceb58

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It does look low. I have my boat out of the water. I will snap a picture of where the water line is on the back of the log. I have a 90HP motor hanging on the back of mine which should weight it down way more than yours. I also have 2 batteries at the back.

Possible that a short 16' pontoon does that and the speed may be characteristic of a short pontoon boat.
 

zalabala

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I have just finished my Tritoon and welded bung vents in each compartment you should be able to get a tig welder to do it at a fair price.
 

Buster_boy

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I noticed the back end just plows through the water. I think the 9.9 doesn't give it enough ooomf to plane out.
 

bruceb58

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I noticed the back end just plows through the water. I think the 9.9 doesn't give it enough ooomf to plane out.
My 90HP doesn't even make my pontoon plane out. Bottom line, pontoons don't plane.

Here is my pontoon's water line. Even lower than yours.

20161102_081514.jpg
 

Buster_boy

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If pontoons don't plane, then why do I see other twin toon boats riding perfectly level (within reason) on the water? The water lines on mine have been there long before I bought it last year. I think the half toon I have in front is keeping it from riding level. I'm going to remove it before next season so we'll wait and see.
 

Scott Danforth

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pontoons dont plane until you get a lot of power behind them. Bruce has stated that prior. another case in point a few members on here went from 50hp to 90hp thinking they would go faster.......wrong. they just burned more fuel and made more noise.

not until you get lifting strakes, and a fair amount of power to actually get the pontoon up and moving to transition from displacement speed to planing speed. hang a 115 or larger and the pointoon starts to get on plane. on a tritoon, your chances are better.

a 10hp on a pontoon wont have a chance in hell of getting a pontoon on plane.... ever (unless your pontoon weights less than 300#). a 10hp on a pontoon is for putting along at displacement speed to go fishing and sight seeing.
 

MH Hawker

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mind if ask why being a bit low in the back matters, its very common slip 1.JPG
 

Buster_boy

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Well, you can tell me that all you want but I know what I see when I'm on the water. Where I boat it's restricted waters - 9.9 and below. I see boats bigger than mine going faster than me and they're perfectly level while doing it. No other boat on that lake sits like mine nor do they plow like mine. Science and engineering be damned, I know what I see.
I'm done here. I thank you all for your input.

Jim
 

jbcurt00

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Bigger 'toon probably has a lower weight per running foot of pontoon.

W no pix of boats you're comparing yours to, it could be that they're running a 9.9hp only, no extra weight of the 40 hanging off the back. Layout of the helm and loungers compared to the centerline of bouyabcy may also effect how your 'toon sits, rides or plows thru the water compared to others. Esp comparing different length and makes of boats.

Most have offered advice and evindence of why they replied the way they do.

You dont like what was offered, well fortunately it cost you nada.....

I'm done here
sort of takes the Thanks out of your thank you....

3rd topic about your unlevel pontoon ends w no resolution. Keep digging, you might find a eureka solution....
 
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