Should I put my gas tank.....there?

sutor623

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Sup guys as some of y'all know I am pulling floors and transom off my '86 16' Starcraft. Now I was going to see if I could rig up a belly gas tank for the center of the boat below deck. Well there's not enough space, so I got to thinking. I pulled my side gunnel extensions out and the aluminum cubes out from under the splash well, and there is a perfect place for this tank 14 Gallon Permanent Boat Fuel Tank, 18"L X 11.75"W X 16.25"H - Moeller 032514 - iboats there is an insane amount of flotation foam on this boat so I am thinking of replacing the foam with a permanent gas tank. Any input on the subject?
 

sutor623

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Re: Should I put my gas tank.....there?

Ill get some pics up in the am. It's just a 16" aluminum ss
 

sutor623

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Re: Should I put my gas tank.....there?

Oh and do these moeller tanks have any way to run a gas gauge from them?
 

GA_Boater

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Re: Should I put my gas tank.....there?

The sorta circled thing is the gauge sender.



ESIT - Are you sure the splashwell has more than 16.25" clearance. More than the height of the tank because you need to to make connections for the fill, vent, sender and feed. A lot of tanks don't include the fill, vent, etc in the measurements.
 

sutor623

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Re: Should I put my gas tank.....there?

The sorta circled thing is the gauge sender.



ESIT - Are you sure the splashwell has more than 16.25" clearance. More than the height of the tank because you need to to make connections for the fill, vent, sender and feed. A lot of tanks don't include the fill, vent, etc in the measurements.

Cool Georgia thanks man! So the electric fuel sender is part of the tank and not something else I have to buy? And yea the tank will fit if I leave the floor out under the splash well to the right. Ill send some pics during the install.
 

jigngrub

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Re: Should I put my gas tank.....there?

Don't overestimate the amount of floatation in your boat, manufacturers never puy in too much foam.

If you remove foam from one place you should put as much foam as you removed back in the boat someplace else... and the last place I'd remove foam from is the stern area, it's there to counterbalance the weight of your motor and to keep your boat floating level if you take on water.

Maybe consider modifying your bow deck to accept a fuel tank instead, it'll be less weight in the stern area and maybe even give your boat a better ride with that weight transfered to the front.

-or-

Consider modifying/enlarging your rear deck to accept a longer narrower tank like this 13 gal.
13 Gallon Permanent Boat Fuel Tank, 32"L X 10.19"W X 10.19H - Moeller 032513 - iboats
32" wide by 10.19" deep by 10.19" high you'd only have to make your rear deck 1' longer.

My 17 gal tank hides under the rear casting deck along with a baitwell and the 2 batteries:
DSC02205.jpg


... and it hides like this:
reartank_zpsc16d2e86.jpg
 

sutor623

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Re: Should I put my gas tank.....there?

That looks badass man!
 

grzzzz

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Re: Should I put my gas tank.....there?

I wouldn't give up on the under the deck tank yet. Moeler makes a tank that will fit nicely in your 16' (I think, I have an 18') and keeps your CG right and weight off the back. boat_005.jpg Filler hose exits nicely on top of the front top deck and vent out the side just below the deck. Comes with sensor that connects into existing gauge or an universal. Part # FT1826. Putting that much weight on the a** end will be like setting the 2 fat ladies on the transom!

Grzzz
 

grzzzz

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Re: Should I put my gas tank.....there?

Sorry, thought my first mail didn't post, but here is some more info on CG...

Maybe you shouldn't give up on the under deck tank so fast... I have an 18' and i believe the moeler tank I put in mine will fit in yours. When I was doing the calculation in CG change for tank placement, I found setting the center on the tank at CG was the most efficient and least amount of impact when placed over CG. Over all and front to back made no difference with a full tank or empty. Would make the most consistent ride and performance. The filler opening went in nicely in the top of the front deck and the vent tube just below it up on the outside. It came with a sending unit that connected right up to the original Starcraft gauge. The Moeller is #FT1826. I have more pics if you want to see the final installation. Not much to see cuz it is all under deck. Pic of the first "sizing-up" boat_005.jpg

Grzzz
 

sutor623

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Re: Should I put my gas tank.....there?

Thanks for the input Grzzz, didnt realize that you had commented until today.
 

sutor623

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Re: Should I put my gas tank.....there?

I think that tank is a bit too wide, but I have to remeasure. The FT1498 is 43" long, 15" wide and 6" tall. Hmmm, opens up my original ideas again.
 

sutor623

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Re: Should I put my gas tank.....there?

And sure I'd love to see the finished installation!!
 

jigngrub

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Re: Should I put my gas tank.....there?

It's probably just me, but the thing I really really hate about the below deck fuel tanks is they block off bilge drainage down the center of the keel... and when you see a resto on a boat with a belly tank, guess where most of the wet foam and/or rotten wood is.

I'm sure one can be installed correctly to ensure drainage down the keel, but most people and manufacturers don't/won't take the time to do it right.
 

chriscraft254

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Re: Should I put my gas tank.....there?

You don't want any fuel tank sitting on the hull anyway, it should be above the hull skin some, which will provide dranage under it as long as you make a drain and not fill it to the bottom with foam. Not sure I would want a fuel cell in the bow as it is where the boat rides the roughest. Center of the boat is usually optimal so your not adding weight in the stern to much.
 

jigngrub

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Re: Should I put my gas tank.....there?

You don't want any fuel tank sitting on the hull anyway, it should be above the hull skin some, which will provide dranage under it as long as you make a drain and not fill it to the bottom with foam.

The foam is exactly what blocks the drainage. The foam is installed after the tank is set and poured all the way to the bottom on all 4 sides between the gap between the tank and stringers/bulkheads. The foam has to be poured all the way to the bottom to hold the tank up off of the hull and support it.
 

sutor623

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Re: Should I put my gas tank.....there?

Hmmmm I see why people just use above deck tanks. I hate the weight in the stern though because it causes porpoising pretty badly. I put a 12 gallon tank under my console to see if it balanced the weight better and it did, but obviously that wa just a test and not a permanent fixture....
 

chriscraft254

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Re: Should I put my gas tank.....there?

The foam is exactly what blocks the drainage. The foam is installed after the tank is set and poured all the way to the bottom on all 4 sides between the gap between the tank and stringers/bulkheads. The foam has to be poured all the way to the bottom to hold the tank up off of the hull and support it.

The foam does not have to be poured to the bottom to hold the tank. The tank should be straped and shimmed as needed, then the foam put in. Some people use the foam as you said, but it doesn't mean its the right way of doing things.

Its very easy to create a channel using multiple different products so you have drainage under the foam. Some boats don't use any foam around the fuel tanks.
 

jasoutside

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Re: Should I put my gas tank.....there?

That would be a great move if you can get a tank sub deck in a 16 footer. Many guys have tried but it's tough to do as there is so little room under there, eh.

Good luck!
 

jigngrub

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Re: Should I put my gas tank.....there?

"Belly" tank factory installation on an '85 Wellcraft:
wellcraft_zps53eaf4b9.jpg


Pretty typical from what I've seen in the restorations will belly tanks.

I wonder how far that foam goes down and what kind of drainage provisions were made at the keel?
 

chriscraft254

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Re: Should I put my gas tank.....there?

"Belly" tank factory installation on an '85 Wellcraft:
wellcraft_zps53eaf4b9.jpg


Pretty typical from what I've seen in the restorations will belly tanks.

I wonder how far that foam goes down and what kind of drainage provisions were made at the keel?

Yup, pretty typical, shotty work,lol If you notice there is a pvc drain pipe in the front, at the keel. Most boats have this to drain water from the bow to the stern or from anchor locker to the stern. Also if you notice, there is room around that pipe where there was not any insulation. Most tanks by building regulations have to be completely sealed off by bulkheads etc. They will not have a drain directly from the fuel tank area because it can lead to a fire hazard if the fuel tank ever leaks. Thats why drains like pvc are used to go under the tank at the keel. The only part of the boat that should not drain to the stern is the fuel tank coffin.
 
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