Glen-L.com

as i was reading the Gougeon Brothers on Boat Construction, i noticed they mentioned building fuel tanks for both gasoline and diesel out of plywood and epoxy. has anyone done this? it seems that it would be a superior use of space, possibly more fire retardent, as wood is a better insulator than thin plastic or metal (although if you are on fire you have bigger issues at hand) and way more economical. my question is how long will the epoxy hold up with gasoline. forever? they mentioned they have been doing it for years with excellent results. and im sure it would be very difficult to get the boat insured with a homemade fuel cell. just wondering if anyone out there has done anything with homemade fuel tanks. they also mentioned making any type of holding tank (water) out of the same. i wonder if epoxy would be safe for drinking water. thanks in advance for any experience based knowledge!
jerry

I seem to remember reading that the coast guard does not allow homemade tanks for gasoline - they require them to have a manufacturers stamp certifying the pressure test was performed, date, etc.

Don't trust my memory on this however - research it before you go to the trouble of building it though. I have also heard that the ethanol in todays gasoline may affect epoxy more than it did before ethanol was added. Again, I'm not sure how accurate the info (or my memory) is.

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Tom
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Knot-So-Fast (A stretched Bo-Jest design)
Travel Log at www.tomstug.blogspot.com

"It's amazing what one can do when one doesn't know what one can't do." - Garfield

Getting a homebuilt boat insured varies and rarely depends upon the type of fuel tank. This is an area that scares the heck out of me, no matter how good of a woodworker a person is and does when building their own boat. In small craft there is no real advantage in building your tank, especially if you are looking to save money. As far as maximizing space usage, this is an area that you can build around a particular factory tank when building your own boat. Also keep in mind that if a person is building a small runaboat, you may fine the need to shift a fuel tank around too after you finish your build, speaking of not knowing what you are considering to build. If you actually build in any tank and have a problem, you will probably need to tear out some good stuff thats unrelated to the tank to fix it.

While West Sytem does speak about it, I feel that in the context of their recommendation they cover a wide range of readers and that you can save some money for the larger applications and when building custom larger crafts too. If you are concerned about the thickness of factory tanks, the only real issue with plastic tanks is that you need to make sure you have room for expansion. When using aluminum tanks, the favorable approach to deal with any and all corrosion is to coat the tanks with a barrier coating.

The costs of failure and leakage of homebuilt tanks goes past simply smelling any and all leaks to the issue that we have open wiring connections and even accessory bits and pieces to consider, which includes inboard motors too, if applicable. If a person is running a two stroke engine, the oil blend can create a messy film which will need to be cleaned up too. There are just some things that needs to be left with the pros, which do it all the time with about a 75 percent success rate in most case, at the worse.

I remember the ethanol thing also. Water and waste tanks are fine. Be sure to clean the amine out of the water tank.

Bill

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Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
Tahoe 19 Build

Here is some information about fuel tanks from the "new boatbuilders page"
Here is the website http://newboatbuilders.com/pages/fuel.html
FUEL TANKS

I strongly recommend that anyone building boats with permanently installed gasoline tanks not build their own tanks. The reason is simple. You have to certify that whatever you put in this boat meets Federal Regulations. Fuel tanks have to meet a whole raft of rules, both USCG and US EPA, and unless you are setup to test them it's better to just buy them from someone who has already tested and certified the tank.

The same logic applies in other countries that use the Recreational Craft Directive, or the ISO standards. It is much easier for a boat manufacturer to buy tanks from a tank manufacturer who certifies that the tanks meet the standards that apply in that country, than it is to build your own and go through the lengthy and expensive certification process.

Here's a list of the USCG tests that tanks have to meet. See 33 CFR 183.501-183.590

The 2 ½ minute fire test: Under very specific conditions the tank has to survive a fire for 2 ½ minutes. The test setup for this is not cheap and only a few test labs have one and know how to perform the test.

Slosh Test:

Pressure Impulse Test:

Static Pressure Test:

The tank must be capable of passing all of these tests. If it passes the Static Pressure test it must have a label that says; "This tank has been tested under 33 CFR 183.580" which means it has passed the static pressure test. There is more information that needs to be on this label. See labels

Also, if you are planning to put the tank in the forward half of the boat it has to meet additional requirements. Tanks that don't meet those requirements have to have a label saying "Must be installed aft of the boat's half length."

Gasoline tanks cannot be integral with the hull. That means that the hull cannot form one side (or more ) of the tank. Tanks must be separate from the boat structure. and cannot support a structure or deck. Some boat builders do use integral tanks but only on diesel powered boats. Diesel fuel tanks may be integral with the hull.

Additionally, plastic (cross-linked polyethyelene, roto molded) tanks have to meet EPA requirements for evaporative emissions and be labeled by the tank manufacturer.

So, go buy a tank from a tank supplier.

Jerry, you didn't mention what size tank you need, but if you Google "spun aluminum fuel tank," you'll see these things sold by most of the off-road vehicle suppliers. The largest I've seen is 13 gallons. I installed a nine-gallon tank in our Zip and it's worked out really well. As delivered, these tanks have a fuel port in the bottom, and I permanently plugged this and welded a threaded bung to the top that will accept a dip tube. I did this to avoid having any head pressure from the tank on the fuel line. I added a second port for a vent line that terminates well above the tank, to allow a sealed filler cap to be used. We can run all day without making a trip to the gas dock, and the boat doesn't smell like gasoline as it did with the old, six-gallon Mercury tank. You can see our installation in the Customer Photos.

I would be really reluctant to build a tank from fiberglass, especially if it's for gasoline. I've heard a lot of horror stories about ethanol softening the epoxy and putting debris into the fuel system, or worse, causing fuel leakage into the bilge.

-Mark Shipley

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A boat is just a wooden box with no right angles.

there is many custom tank fabrication shops in existance. you can draw up a sketch of what you need, and get a price quote confirmation. I think it better to either buy a custom tank, or, build around a stock sized tank.

just my $.02

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God Bless our Troops; especially our Snipers

Going to have to name that boat "puff the magic dragon", or "Boom" - because that is what is going to happen.


Why would anyone want to go for a nice gentle ride around the lake in their very own thermobaric bomb? A gallon of atomized gasoline produces 5Mj of energy, roughly equivalent to .75Kg of dynamite.


plywood fuel tank is an epically bad idea.

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Some plan to stroll through Saint Peter's Gates, I plan to go through them at 150mph... backwards... in a screaming ball of flame, with a glimmer belt wrapped around my head, and a NOx button in my hand.

This thread can be defined as an explosive subject.

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John Amundsen
Monte Carlo
Winter Haven, FL

Maybe it will be done by G6 and maybe not.

I gotta say, I'm with pamelalynne1 on this one and not trying to be incendiary in any way.

I merely pointed out some of what the Coast Guard and EPA requirements are fo fuel tanks. The boat could be named after a breakfast cereal. KABOOM. When I was about 11 years old I remember a boat going up on Lake Hopatcong. It was an Evinrude outboard with a pressurized tank and the fuel line started to leak. Somehow a spark ignited it and that nice lapstrake Lyman was half gone by the time the fire boat got there. We picked the young couple up out of the water. They were OK. Thankfully, no explosion.

great info guys thanks! i wouldnt have the nerve to trust a homemade wooden box but it was a neat thought for a pair of 40 gallon tanks. im going to stick with plastic or aluminum for sure.

From personal experience I can state that ethanol and epoxy tanks are a recipe for failure. Here is a couple of links to my blog pages where I ran a test and had a tank failure -

http://egyptian.net/~raymacke/Cbnskif27.htm

http://egyptian.net/~raymacke/Cbnskif36.htm

Also, here is a report from BoatUS that confirms my findings. Although it it mostly about polyester resin near the bottom they talk about epoxy -

http://www.boatus.com/seaworthy/fueltest.asp

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So Many Rivers,
So Little Time....