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Race fuel storage solution?
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Posted by: Masterphil---------------------

Race fuel goes bad because the light ends evaporate from the fuel(loss) and because of free oxygen in the air(oxidation).

Plastic containers allow fumes to permiate, not a good idea for long term storage. So the container must be made of metal. How about a stainless steel beer keg? Stainless steel is defenitely capable of handling race fuel. Another benefit is the keg is designed to hold pressure, unlike a steel drum. A keg would hold 15.5 gallons or fuel. So 3 kegs and a 55 gallon drum leaves you with 8.5 gallons of fuel to start using.

Since air containes oxygen, the fuel will become oxidized unless the head space in the keg is taken up by some inert gas. Nitrogen is one choice. But, what about CO2? CO2 is a much cheaper and safer gas to store and use than nitrogen.

So we have a beer keg full of race fuel, how do we get it out... Use the CO2 tank to push the fuel out of the keg and through a standard stainless steel beer tap, just as done in kegerator setups that thousands of people and bars use everyday to dispence beer. Doing it this way will give you fresh fuel in whatever quantity you want it without comprimising the freshness of the rest of the fuel.

I only thought of two reasons why this might not work:

1) CO2 may react with the race fuel, but I don't think it will. It is used as a shielding gas for mig welding steel, the idea is to prevent oxidation.

2) The race fuel will become carbonated. I don't think this will happen either. Race fuels are petrol based, not water based. The only reason why so much CO2 readily dissolves into water is because it will turn from dissolved CO2 to carbonic acid, and finally into the bicarbonate and carbonate ions. This allows a very large quantity of CO2 into a given volume of water. The CO2 shouldn't do this in any other liquid besides water.

So, what do you guys think about it? Seems like a perfect way to make sure that expensive oxy-race fuel stays fresh until you need it.

Posted by: biglou---------------------

FWIW, I've let some NON-oxygenated race fuel sit in a half empty 5gal metal container in my garage for a few months (over winter, dark and cool/cold) and still ran it just fine in the spring in the 05 YZ250. If it would have sputtered or acted strangely in any way, I'd have dumped it immediately.

Posted by: Kav---------------------

While I'm not sure it would work, if it did having gas on tap would be awesome! until someone get's drunk and thinks it's beer...

Posted by: Masterphil---------------------

I guess all that's left is to buy a keg of beer and start drinking

Posted by: Jaybird---------------------

I think there is more concern with the H2O content of the air in the headspace, than the oxidation of the fuel. Also, the larger the headspace, the more chance of loosing light ends.
An inert gas filling headspace will work, but clean dry air is also an option.

There was a thread on this very topic a couple of years ago that went very indepth with this discussion.
The prospect of vacuum was also discussed.

I personally have some jerry cans rigged with a Schrader valve and a pressure guage. I use dry air at low pressure. Nitrogen could also be used, but I filter and supply myself with dry air for free.

Posted by: mtk---------------------

Beer kegs are aluminum, not stainless steel. Except for the rubberized ones used by Miller Brewing, but those are the exceptions.

I'm also not sure why CO2 is "safer" than Nitrogen. Cheaper, maybe, but the Nitrogen tank could also be used on suspension components, while the CO2 is only good to pump beer kegs (which isn't a bad thing, mind you).

You mentioned methods to get the fuel out of the keg; how are you going to get it IN the keg in the first place? I don't know if the standard tap mechanisms on a beer keg will hold up to gasoline or not, but I'd guess that they won't tolerate it too well.

With that said, the old stem tap kegs make excellent dune buggy fuel tanks.

Posted by: Masterphil---------------------

Jaybird-
I read that thread some time ago. That thread, and the fitting up of my CO2 tank jointly spawned this idea.

MTK-
I was informed that kegs are typically aluminum when I mentioned this to my dad, but since carbs are aluminum, I don't see a problem with this. The reason I say CO2, I already have(will very soon) a CO2 tank mounted in the rig to use for airing up tires and powering air tools every now and then. Why, I can't afford a generator and I want to be non-dependent on electricity. The same reason I'll be using LPG for light, heat, and cooking. I say CO2 is safer because it is stored as a liquid compressed to 800ish PSI, not as a gas stored at 2000+PSI. The CO2 tank will also last a very long time. Fifteen pounds of liquid CO2 is about the same as 1000 gallons of air(or 134 cubic feet). It would take quite a large nitrogen tank to last as long as my 6" round 27" tall CO2 tank will. The only benefit nitrogen has is use in suspension components, but I have a KTM and don't think I want to mess with trying to bleed that PDS shock.

I'll get the fuel into the keg the same way a home brewer gets beer into the same keg. I'll disconnect the transfer line from the tap and pour it right down the neck of the tap. Thanks for bringing up a point I hadn't considered. The only piece of non-fuel compatable rubber will be the tap-to-keg gasket. Keg is aluminum, tap is stainless steel or chromed steel, transfer line can be reinforced fuel hose, and the faucet is stainless or chromed steel. I'd probably have to have that gasket made, or make one myself from a fuel compatible rubber or thin slice of large diameter fuel hose.

Posted by: Jaybird---------------------

Phil,
Go to a farm supply store and look at a well water pressure tank.
You will be better off trying to rig one up as they have threaded couplings already welded in for you to use.
Rig it up correctly and you can use the pressure of the inert gas to push the fuel out.
I suggest the exit tube rigged so it is submersed in the fuel with a screen end.
If you have seen a refillable water type fire extinguisher, you will get the drift of what I am saying.

Posted by: mtk---------------------

Quote:

Originally Posted by Masterphil

I say CO2 is safer because it is stored as a liquid compressed to 800ish PSI, not as a gas stored at 2000+PSI. The CO2 tank will also last a very long time.

I'll get the fuel into the keg the same way a home brewer gets beer into the same keg. I'll disconnect the transfer line from the tap and pour it right down the neck of the tap. Thanks for bringing up a point I hadn't considered. The only piece of non-fuel compatable rubber will be the tap-to-keg gasket. Keg is aluminum, tap is stainless steel or chromed steel, transfer line can be reinforced fuel hose, and the faucet is stainless or chromed steel. I'd probably have to have that gasket made, or make one myself from a fuel compatible rubber or thin slice of large diameter fuel hose.

A CO2 tank isn't safer than a nitrogen tank. I'm well aware of the differences in pressures and storage, but the fact remains that both are pressure vessels and can be deadly if mistreated. They both also require hydrotesting on the tanks at the same interval (every 10 years as I recall) so a CO2 tank won't last longer either. If you don't want to take my word for it, ask your compressed gas supplier. I'll bet he'll tell you the same thing.

As for the keg bit, you're wrong on the gaskets. There is a ball valve on the top of the keg and it has a rubber gasket of some sort right on the top of it. Who knows what else is inside it as I've never disassembled one. But I know I'm right on this because I just looked at an empty half keg I have in the back room (I just opened a beer store so I'm VERY familiar with kegs these days). Taps are not stainless steel either and they also have more than one rubber gasket in them. You also haven't identified any method to clean out the keg inside. All of them have some beer residues in them and that isn't what I want mixed in my fuel.

As for homebrewers filling a keg via the tap, if that is true I wouldn't drink anything they produce on a bet. Commercial brewers clean and sterilize a keg before they reuse it. I'm not sure how one would accomplish that at home, but if you don't you're just creating a nice biology experiment inside that keg.

Posted by: Masterphil---------------------

Well, it's the thought that counts. At least you guys shot me down before I spent money on it.

Jaybird - I think I'll look into that.

Posted by: mojonito---------------------

you can still buy a keg and drink the beer!

Posted by: Masterphil---------------------

Now that's a good idea!

Posted by: motometal---------------------

reading this thread makes me feel better (mtk isn't singling me out at least! ha!)

seriously, anyone have any more thoughts on CO2 dissolving in fuel? What about dropping pellets of dry ice into gasoline? I'm not thinking of this idea just for the storage application, but to cool the fuel for riding/racing.

At what temp does your average premix freeze? Dry ice is around -100F. If exposed to air (containing water) or water in the fuel, the dry ice could form a shell of (water) ice on it.

I was considering somehow putting the dry ice directly in the fuel tank, another option to cool the fuel would be making a closed loop heat exchanger, probably with a solution of dry ice and alcohol in a canister.

Posted by: Rich Rohrich---------------------

Quote:

Originally Posted by motometal

another option to cool the fuel would be making a closed loop heat exchanger, probably with a solution of dry ice and alcohol in a canister.

MM- It's called a Cool Can. They been doing that in drag racing since the 60s (maybe longer).

http://www.moroso.com/catalog/categ...p?catcode=32030

Posted by: motometal---------------------

well great, I just reinvented it

What do you think would happen with the dry ice directly in contact with the fuel?

Would you recommend a fuel with a different dist. curve when running a "cool" setup?

Posted by: Rich Rohrich---------------------

Quote:

Originally Posted by motometal

well great, I just reinvented it

What do you think would happen with the dry ice directly in contact with the fuel?

Never gave it any thought really, but contaminating the fuel with anything foreign seems like a bad idea at first glance.

Quote:

Originally Posted by motometal

Would you recommend a fuel with a different dist. curve when running a "cool" setup?

Most definitely. I've really only looked hard at it on four-stroke engines, but dramatically lowering the fuel temps tends have a cumulative effect on lowering the surrounding port surface temps. On short runner engines that turn high rpm that makes fuel metering tricky unless you account for it.

Logically a two-stroke would seem something similar, but with the longer path the fuel travels and the effects of crankcase compression I'll hazard a guess and say it will probably be a bit more tolerant of the fuel characteristics. Either way it would be interesting to investigate if you have the time and the desire. Whether or not it proves to be worth the effort remains to be seen.

Posted by: 2strok4fun---------------------

Back to the beer keg-

Most are stainless, at least all that I have come accross. I use a AB beer keg as my boiler for home brew with the top cut off, its all stainless. As for the bung, I dont know all the materials that are in there, I dont use the large kegs for storing/serving.

I have however used the 5 gallon cornillius (sp) kegs that I had many of to store fuel in. They are made of stainless have stainless dip tubes and the tops open to approx 3x5 to allow filling, I then stored it on ~6 lbs of nitrogen using my same pressure regulator used for the beer. Worked well tho I havent stored fuel using N since my last bottle escaped thru a fitting that didnt seal completly. I used standard O-rings that held up well enough as there isnt direct contact with the fuel if the keg is stored upright. The bigest drawback was with the small dip tube, the flow rate was too slow to use as a daily container and I only used if the fuel was to sit more than a week. The dip tube could be changed out to somthing like 1/2" with some part collecting or even weld on a new port, but I havent done it.

I have wondered about CO2 and if it would even be able to disolve into the fuel, never tried it tho.

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Race fuel storage solution?

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