Jgrabe

I am having a 35 gallon fuel tank installed below deck in my 17 1/2 foot fiberglass skiff. The tank is going to be in contact with the fiberglass hull, unless I put some sort of shock absorbing material between the metal tank and the fiberglass.

What should I use to lay beneath the tank? The person doing the install talked about cutting a 1" hose and laying it open and somehow securing it.

Any other ideas?

v12mac

Lots of rules and regs about this kind of work. Are you "having" it done or are you doing it yourself?

Jgrabe

It is being done for me.

But I want to be sure it is being done the best way...

I am getting a quality aluminum tank. The person that is installing it will be tacking it down with foam, but not "foaming it in".

Jonesy23

From my searches, 5200 some neoprene strip to the tank and then to hull.

parrott

Here is a good article from David Pascoe.

http://www.yachtsurvey.com/fueltank.htm

CapnDean

I have done this several times. Don't know what the experts will say but I glued strips of poly to the tank and bedded it in 5200. When my 19'6" aquasport tank gave out, I was taught that the foam holding it in trapped water and caused the tank to give up prematurely. The trick is to have it where it can get wet but then get dry. Air space - block it in so that it cant move around on ya, but above all don't let wood that can hold water wedge it in. Just use strips (batten's chocks etc,)

Good luck

Cobia 217

Small tank, so why not a Moeller poly tank and never have to worry about it again? Use strips of neoprene sheet gasket at contact points.

Jgrabe

Thanks guys! The tank is 6" x 24" x 46" or close to that. It is a very narrow space and a custom made tank out of Ezell Industries in Perry, Fl.

I will check out the article, and look up the material listed above. The Tank will have no wood nearby, other that the bottom side of the deck, and will have an access hatch as well as a drain, to keep water from accumulating.

Absolute

6x24x46 = 28 gallons

Tanks we install are either held in place with rubber like restraints or foamed in. Most important is to allow water to get away from the tank, add a drain from any forward areas to aft area by routing it through pipes or tubes under the tank.

Jgrabe

I must have the dimensions slightly off, It does drop to 7" down the center. Either way it is 35 gallons.

The area of concern that I have is that since it is basically laying on the hull, unless I put an shock absorbing substance between the hull and the tank, that the vibration may cause it to fail.

So far the best I have heard was Neoprene. And tack it in place with foam. I am just concerned about vibration, it is a flat bottomed boat (for the most part, a slight tunnel through the center about 2" deep and 3' wide) and rides rough in choppy water.

thataway

There are a lot of good suggestions above. You do want to isolate it from the hull, yes. You do not want to use any material which has carbon in it. Neoprene is an excellent material, as is 5200. I also favor coal tar epoxy over the bare aluminum to prevent corrosion. I would avoid any foam--they all seem to hold some moisture (I know, some foams do not retain water…sure…) Moisture and salt, will eventually damage the tank, unless protected.

The materials which are suitable are: Neoprene, Teflon, High density plastics.

Unsuitable, foams, carpet Wood, felt, etc.

jeffnick

Neoprene strips 5200'd to the bottom of the tank is how I did it -- as recommended by my aluminum tank mfgr.

Absolute

We placed two 200 gallons in a boat today setting on Skirtboard from Goodyear Rubber. They run end to end of the tanks and are 1" wide.

jpv

I am probably wrong but isnt neoprene what wet suits are made of? I thought neoprene was the spongy stuff that is porous.....I use solid rubber strips sold to me by the tank mfr. He said to 5200 the strips to the tank leaving no air bubbles between the rubber and the tank........they also wanted me to build a little platform for this particular belly tank to rest on for the bottom portion. I can see how neoprene would be better for shock absorption.....but no good if it holds water......I was thinking its like the old open cell foam vs the new closed cell foam........