Pressureized gas tank

Anonymous-0 · May 8, 2013

I'm in the process of building a "tractor" and because of some design limitations the middle of the gas tank will be approximately carburetor level. I plan to pressurize the tank with a small hand pump (1-3 psi)to utilize the entire tank of gas. I'll make the lid air tight. Do any of you good folks see any problems with that arrangement. The tractor is close to being finished and when it's running I plan to have some pix on this forum. To say the least I think it's unlike any tractor you've ever seen. Thanks for any ideas/experiences anyone might have had with this subject.

paul · May 8, 2013

That's one of the funnier messages I've seen on here, thanks for the chuckle!

Needed that tonite.

Paul

Determined · May 8, 2013

Not a good or safe idea.
At the very least you would need some kind of a vent, when the sun shine hits the tank you will have a lot more than 2-3 PSI.
If you have a fuel pump on the engine, why not utilize a fuel pick up tube inside the tank to draw fuel from the top of the tank.
If you do not have a pump on the engine a diaphragm electric inline pump could be used along with an oil pressure switch and relay to control it.
A pressurized system would need a flawless needle and seat in the carb or you risk pushing all of your gas onto the floor with a updraft or sidedraft carb, a disaster waiting to happen in the case of a fire, bad hose or clamp, filter, fitting etc.
If the engine has a down draft carb in addition to the other risks listed above, you risk washing out your cylinders and filling your oil pan with gas, Not a good thing.
Dave

robgIN · May 9, 2013

you would be much better off to use a fuel pump, bad idea to pressurize gas tank.

John B. · May 9, 2013

1-2 PSI???

Remember how many square inches you'll have on the surface of the gas in the tank and multiply that by the 1 or 2 PSI and you'll have that much force pushing that fuel to the carb. Gas sloshing around in a gas can creates pressure.

You need to scrap the PSI Gas Tank idea...

mkirsch · May 9, 2013

BAD idea. You're basically creating a flamethrower.

Gas has huge changes in pressure with temperature. It will go from sucking the sides of a gas can in on a cool night to bulging them out to the point where the can won't sit flat on the ground in the heat of the day.

Also a simple float style carburetor is not designed to hold back pressurized fuel. The pressure will push the fuel past the needle and flood the engine.

You have other options:
1. Figure out your design limitations to raise the tank.
2. Use a fuel pump to deliver the fuel to the carburetor.
3. Use a smaller tank so it's entirely above the carburetor.
4. Keep the tank over half full.

Greenday · May 9, 2013

Pressurize the fuel tank? BAAAD IDEA!

ldj · May 9, 2013

I saw a guy had about 2,000 gal fuel tank for his farm fuel. He didn't use a pump. He pressurized the tank, I don't remember how much but low. Don't remember details but it worked good, just squeeze handle and out comes fuel.

bobs old iron · May 9, 2013

guess he never heard of LPG tractors,, newbees, geeze

Janicholson · May 9, 2013

A Facit electric pump is cheap, a regulator to take it to 2psi is cheap. Reentry from suborbital velocity requires parachutes. Jim

Anonymous-0 · May 9, 2013

Use a fuel pump. Imagine if the tank sprung a pinhole leak and was spraying vaporized fuel out on the hot engine.

Anonymous-0 · May 12, 2013

ouch, you took a whooping by some for that innocent question didn't you? makes me think a few of them have never cut hay on a hot summer's day with a gas tractor. that said, a pump would be the way to go.

Pressureized gas tank

Anonymous-0

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paul

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Determined

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robgIN

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John B.

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mkirsch

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Greenday

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ldj

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bobs old iron

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Janicholson

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Anonymous-0

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Anonymous-0

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