New guy and I have a question about flotation pods.

Hello everyone,
This is my first post on here and I don't know if it is in the correct location or not.
I am thinking about ways and places to add a large livewell to my Lowe 2070 (aluminum jon boat). I am looking at adding it to the back of the boat but I am concerned about the added weight. I was looking at adding a set of flotation pods to help counteract the added weight of a 40+ gallon livewell full of water.
From what I can find out on line, pods will add 200-300 pounds of lift. Considering 40 gallons of water would be 320 pounds. Would a set of pods be the way to gain back (so to speak) the draft lost with the added weight.
Any thought on this or shared experience would be much appreciated.

Thanks
David

 

On top of thinking about gaining back freeboard, you should think also about stability issues. A live bait well, located over deck will surely raise the COG, as well as further reduce stability because of the free surface effect. Be careful.

 

Hello and thanks for the reply,
I should have made my post a little more clear on what I was intending to do with the live well. If I add the live well it will be cut into the rear deck and would not be put on top of the rear deck. The two side areas in the picture (attached) are labeled flotation foam and that is all that is in that large area on each side. In the center there is nothing under the area between the foam on each side except the fuel tanks and I have just over 12 inches of depth from the top of the fuel tank to the deck.
After more measuring and a little more thought about what would be practical (easiest). I am thinking of building an aluminum live well that would measure 48 x 15 x 12 and would have a water level capacity of 10 inches in height (to the bottom of the overflow). That tank should hold approx 31.17 gallons of water. That would translate to approx 250 pounds. I can make the tank bigger but I don't think it will be necessary. I could relocate the fuel tank to under the center console or under the front deck and make the live well much larger (50 gallons +).

Sorry I did not make my plans clearer in the first post.
i am looking at the flotation pods to keep the draft on the boat close to or better than it is now.
Thanks again for the help,
David

 

Dav,
Have a look at:
http://www.boatdesign.net/forums/showthread.php?t=16624
http://www.boatdesign.net/forums/showthread.php?t=17119
http://www.fisherbeavertail.com/floatationpodsintro.html
Cheers.

 

Thanks, I had found the first link and the last link but I don't think i have read the tread in the second link.
Thanks again for the help,
David

 

One other consideration. Your boat has level flotation. That is if it swamps it will remain afloat and float fairly level. The amount of flotation is based on the weight of the boat, the maximum weight capacity and the weight of the outboard. You would be adding 250 lbs to the boat weight near the aft end of the boat, which would require close to 4 cubic feet of 2 lb density foam flotation to compensate for the added weight. In other words your boat with the added weight will no longer float level and may not stay afloat when swamped at all. Now if those pods were filled with foam or sealed airchambers, that would compensate for the added weight if the boat swamps.

Here's a link on level flotation http://newboatbuilders.com/pages/flot2.html

 

Ike,
Thanks for the information. The rear pods would be sealed boxes and welded to the transom of the boat. I am also strongly considering filling them with closed cell flotation foam for a couple of reasons. The first reason being in case one of the pods ever had a leak. The second reason is I would be removing a small amount of factory foam. That is what got me to thinking about putting foam back into the pods. The pods full of foam would be much more foam than I would be removing from the factory foam.

The two hundred and fifty pounds would be in water in the live well. Nothing more than would be in the same area of the boat it it were swamped. Correct?
So would this make my boat go noise down if it were swamped?
I would think if the boat has the correct amount of foam from the factory and it is the required amount to float the front of the boat than it would not change if I added foam to the rear pods. ??

Thanks again for the replies and help.
David

 

Probably unnecessary to say it, but you have to carefully make sure you gain back all lost freeboard by means of the pods. Otherwise the allowed maximum load (crew and equipment) of the boat should be reduced. Ike for sure may advise you on this.

 

I really appreciate the replies and help with this.
Should I make the bottom of the pods even with the bottom of the boat or should they be raised about an inch from the bottom of the boat?
Should the inside edge of the pods be angled like in the first picture below?
Or
Should I square the inside edge of the pods or angle them like the ones in the second picture below?
I have a manual jack plate (6 inch set back) on my boat that will help with clearence and to get the motor back into clean water. I think?
Tha last two pictures are of the back of my boat, and the jack plate.

Thanks again for all the help and sorry for all the questions.
David

 

Recognizing my lack of practical expertise on this matter, I'd even the bottom of the pods with the bottom of the boat, and angle the inside only as necessary because of the turning angle of the engine.

Cheers.

 

Thanks for the info.
I read somewhere that the angle on the inside edges would hurt the performance of the prop. Does anyone know it the angle and re-direction of the water flow would be an issue?
Thanks
David