For all gas pilots!

[beto9]

There are now a lot of posts in the US about using gas with some percentage of alcohol in their gas planes. It seems the alcohol slowly ruins all rubber pieces in the engine and specially carburetor.
Their solution is, if you don't know if there is alcohol or not in the gas you buy at your unfriendly service station, to get aviation gas at the local airport. More expensive but pure.
So.... keep checking your rubbers (pun intended)

[Mick]

Ethanol in gas in increasing in both USA and Europe under legislation designed to reduce global warming. Originally it was set at 5% but this is due to rise to 9%, if I remember correctly. Manufacturers are objecting for just the reasons you are stating. However, there is now a growing movement in Europe to reduce or eliminate the Ethanol as it is now proven that it is a negative impact on global warming. The logic goes something like this:

Generate a demand for Ethanol by legislation
Farmers divert land to Ethanol production from food stock, food prices soar
Governments introduce incentives for more Ethanol production from non-food stock.
People plant Sugar Cane in Brazil, Indonesia etc to make Ethanol solely for Gas dilution. Ethanol prices still rising.
Not enough land available, so people burn down rainforest to grow more sugar cane to make Ethanol for our cars. The payback period for this is 300 years in impact on global warming.

So net result higher food prices and faster global warming, a well thought through policy.

Are we supposed to avoid politics on this forum?

[loflyer2001]

:confused: Ethanol contents or no ethanol contents......
With the diaphram pump on the most popular Walbro Carb.
I wonder if it makes much of a difference. For instance,
you stop flying in the fall and in the spring when it is start
up time...well...you will still need to get a new carb kit for
your Walbro carb because it has dried up, stiffened, what
have you because it will not work. Mystery oil injected
into your engine on last run will protect your bearing seals.
Our 2-cycle engines while running, waste a lot of fuel for
cooling off than it burns. 10% or 15%of Ethanol(now available
at the pumps out west) I believe, will not make much of a difference.


My 2 cents worth;
Guy

[Dwight Macdonald]

I heard someone say that aviation gas (avgas) will clog up the rings in our engines because it has lead in it.

[turkana]

Hi Aviation Gas will not clog up the rings.Otherwise it would clog up the rings in aircraftengines to.Actually Avgas burns the cleanest from all and the lead is only used to cushion the valves slamming into the valveseats, since older engines have softer valveseats.The only thing that will clog up rings of a 2 stroke is wrong oil, wrong carb setting.The best gas for 2 stroke model gasengines is camping stove fuel, since the jets on these burners are so small ,they easily clog up with the stuff from the pumps.Regards Pete

[Sunfly]

I knew a guy in the states named Spencer Gardner. He past away 5 years ago.
He was writting articles in magazines when he was active.
I saw him a couple of times at my father's in law club in NY state.

He was flying only with what Americans call white gaz which is naphta.
So I think that this could be the solution. Now will there be lead in that naphta ?
I don't think so. Is it that much more expensive than gaz ? To be verified.

My 2 cents,

Cheers,

[Jeremy Cartlidge]

It is amazing how governments happily subsibize industry to add a chemical to our motor fuel that increases fuel consumption, attacks seals and hoses, and promotes corrosion in fuel tanks. Any environmental benefits are dubious and probably negative considering that farmland is generally taken out of food production to produce ethanol. We consumers are overly ignorant or compliant in accepting a lower value fuel because of political and commercial interests.

Ethanol provides significantly less energy than gasoline resulting in less gas mileage for the mix. We buy fuel by volume and not by energy content so that we get less value when we fill up with the blend. An engine designed to burn pure ethanol using appropriate fuel system components and optimized for the fuel can make sense in some situations. This mandatory blending is irrational and a ripofff for consumers.

Bob - Unfortunate for your MG. You are likely to see problems with fuel pumps, carbs, tanks etc. Even fairly new cars are going to have some problems unless they are properly designed for the ethanol mix. Older cars, boats, mowers, generators, airplanes etc were not designed to use the blend.

[zorba]

If you do a search on other forums about 2 stroke gas engines you will find out that most use Amsoil for mixing and Coleman camping fuel for their engines. I don't know how much more is the Coleman but once you use it you can't go back to reg gas unless you overhaul the engine.
I think that might worth a try. Gas helis in the house sometimes they smell. The Coleman wont.


Cheers

[Michael V]

very interesting

[Dwight Macdonald]

I would be concerned with using naphtha because the octane rating is likely very low (just my guess though) and many of our gas engines require high octane fuel ... it may cause pre-ignition.

[zorba]

Well guys I did some searching and found this:

Naphtha is used primarily as feedstock for producing a high octane gasoline component (via the catalytic reforming process). It is also used in the petrochemical industry for producing olefins in steam crackers and in the chemical industry for solvent (cleaning) applications.

(as an unprocessed component - in contrast to reforming above) in the production of petrol/motor gasoline.

an ingredient in some lighter fluids for wick type lighters such as Zippo lighters

a fuel for portable stoves and lanterns, sold in North America as white gas or Coleman fuel.
Shellite (Australia), also known as white gas (North America), white spirit or Coleman fuel, is a water white liquid with a hydrocarbon odour. Shellite has a freeze point less than ?30 °C (?22 °F), and a boiling point of 47 °C (117 °F). The composition of shellite is 95% paraffins and naphthenes, less than 5% aromatic hydrocarbons and less than 0.5% benzene. It is highly flammable and due to its low flashpoint is used in many low pressure camping stoves. Shellite is also a fast drying solvent used for cleaning metal, hard plastic and painted surfaces. Ronsonol is a brand name used in North America, and is marketed principally as a refill fluid for cigarette lighters and has a flashpoint of about 6 °C (43 °F).

Gasoline (regular unleaded)[1] 1 US gallon 114,100 BTU/gallon

Jet fuel (naphtha)[4] 0.97 US gallons 118,700 BTU/gal (does this means that Naphtha has higher octane containt than gasoline? I don't kow. But is used to produce High octane gasoline)

Ethanol fuel (E100)[1] 1.500 US gallons 76,100 BTU/gallon

In another words Naphthafuel is very volatile. It burns hotter than gasoline..
My 2 cents
Cheers

[Sunfly]

Well guys I did some searching and found this:

Jet fuel (naphtha)[4] 0.97 US gallons 118,700 BTU/gal (does this means that Naphtha has higher octane containt than gasoline? I don't kow. But is used to produce High octane gasoline)

My 2 cents
Cheers

The extract of the text from Zorba above seems to indicate Jet Fuel is the same thing as Naphtha.

I thought Jetfuel was Kerosene which would be a lot more heavier than naphtha.

I don't know if this principle applies everywhere but the more refined or volatile a petroleum product is the less energy per weight it contains.
I don't know if the relation of high octane vs more refined even exists.

For sure we can say Diesel contain more energy than Gaz.
Oh Ya! Science says otherwise

I checked in the energy density table at Wikipedia.com
and what I read was boggling me and throwing away all my beliefs.
here is the link http://en.wikipedia.org/wiki/Energy_density#Energy_density_in_energy_storage_an d_in_fuel
Scroll down to the second table.

Now how come an engine running on diesel is much more economical to run than a gaz engine if the energy densities are resp. 46.2 and 46.4 Mega J per Kg

Hopefully the Wikipedia table is wrong
My logic is crashing (hopefully not my plane) Help !!!!!!!! :eek::confused:

[Jeremy Cartlidge]

I believe that diesel fuel has a higher energy density than gasoline (by volume) but the numbers are very close. The diesel cycle is more efficient in converting the fuel energy into mechanical energy. Rudolph Diesel was investigating the very low measured efficiency of gasoline engines when he invented the diesel. Unfortunately the diesel needs very high compression and complex fuel systems to work well. They do get much better fuel economy.

[Mick]

The reason diesels are more fuel efficient that petrol engines is not to do with the fuel, purely the cycle. Modern diesels, with or without turbocharging have very high compression ratios 20:1 is typical compared to 9:1 for modern petrol engine. Therefore the thermal efficiency of the machine is better giving more mileage. You cannot raise the compression ratio on petrol engines without pre-ignition or detonation i.e. it turns into a diesel engine. BUT petrol being more volatile has a much high flame propagation rate so it "explodes" on compression ignition whereas the heavier diesel fuel burns, same process different time. The lighter designed petrol engines cannot take the loads produced by detonation so fail rapidly. Octane enhancing additives delay the onset of detonation allowing higher compression ratios.

Jet A1 is kerosene which is a wide cut fuel i.e. it contains both lighter and heavier hydro-carbon compounds. It also contains a lot more sulphur than is allowed in diesel fuel. It is cheap to make and has just about the ideal qualities for aviation. Difficult to light (good in an accident) but with very high energy density, does not absorb water, can still be pumped at -50c. A good demonstration of kerosenes' inherent safety is to drop a match or lighter in a bucket of kerosene, it goes out. Stand well back and try the same thing with petrol. In aircraft crashes that produce fires it is invariably the oil that burns first then heats up the kerosene to produce vapour which then burns. NACA proved this by deliberately crashing lots of ex-second world war aircraft into concrete blocks and metal posts to find out how the fires started, what a job, so they can set design rules for fuel and oil systems. The change of fuel by moving from pistons to jets was a major factor in improving survivability in an air accident.

[Sunfly]

Thanks for the information about the diesel.
About the kerosene trick and the match I tried it in my basement and that is the reason I had to move temporarly to the Holiday In. :D Just kidding

Surprisingly in my crazy teen ager period I did all kind of experiments.
I built a pulso-reactor with an empty solvent can held in a vise, an air supply from a small compressor and a Coleman pump tank. The reaction pulses I obtained was just few milliseconds but what a pow !
Do not try this at home.

An other experiment I did was to kill a match in gasoline.
Here is how to do it. --This is only for the braves.:D --
It was a cool day about 65 F about 18 C with just a little wind blowing from my back, so the vapors will go away from you.
Please Do this outside on a stone surface and away from any combustible material; asphalt will be damaged if you spill !

I put an inch of gasoline in a 3 inches diameter can.
Then you light the match (those were the standard wooden Eddy matches so no cheatting )
you then hold the match as far as you can from the gasoline and you blow in the can to remove all the vapors. Then you throw the match as quick as possible without killing the flamme.
It may not work the first time but with some practice it will do it.
Let it cool off between attempts
Also be prepared with a piece of fireproof board (Gyproc is good, plywood will do) to put over the can to kill the fire.


Be careful and have fun !

[zorba]

I agree with you Luc. Here's another table that shows the difference between fuels in the GGE Gasoline gallon equivalent.

They also have the Jet fuel Kerosene.
Take a look the BTU's they produce and see which is hotter.

Cheers
http://en.wikipedia.org/wiki/Gasoline_gallon_equivalent

[Sunfly]

Ah! Zorba, this is a better table. Thank you.
That also illustrate why we need bigger thanks when we run on glow fuel.
But I have to agree with Alberto:there is nothing like the smell of the glow in the morning.

Cheers,

[zorba]

Ah.... very well said. I agree with you and Albert again.
But I think I can do with out the high price of glow and the clean up afterwords.

So, in conclusion for some of us that are not fortunate enough to have a big house or a basement for that matter, gas is a bit less messy to store and maintain.
Of course I will still keep my glow machines just as reminder to what was like to smell the glow in the morning.

Cheers

[Mick]

Methanol (CH3OH) and Ethanol (C2H5OH) are alcohols so carry some oxygen with them. Therefore their mass energy density is lower than other hydrocarbons without oxygen. So just remember when you buy you next gallon of glow fuel you are paying for oxygen you can get for free.....

Liquid hydrogen is interesting as it has very high mass energy density but very low volume energy density ie you need a lot more volume but it weighs less for the same energy as say kersosene. A lot of people ask why don't we use hydrogen for cars, trains & planes as it is pollution free as burns easily to produce water. The main issue is how to produce the hydrogen, store it and distribute it without causing more CO2 than just using oil. It is not known for its safety record, Hindenburg?? However, a much more fun statistic is that if a 747's fuel tanks were to be filled with liquid hydrogen at the same rate as they fill the space shuttle, which uses the best technology available, it would take two weeks. Airline profitability would look even worse......

[zorba]

Good info Mick.
But I think in Vancouver some of the city buses are using Hydrogen for sometime now.
I think they only had a couple of service outlets where they would gas up.

If I can find the news clip I'll post it here.

Cheers
Bill

[Sunfly]

Lots of things that scare people about hydrogen is a kind of a myth.
Hydrogen ignites easily it is true but:

Modern scientific investigations about the Hindenburg incident tend to proved that the primary cause of the disaster was imputable to the covering paint of the fabric. This paint was made of aluminum and iron oxide. This is what is called thermite. If you ever saw thermite in fire it is almost as scary as a lithium ion battery in fire.

YouTube - Thermite reaction

To have a real good coverage of this Hindenburg disaster:
http://en.wikipedia.org/wiki/Hindenburg_disaster

Here is an extract of the document:
"Proponents point out that the coatings on the fabric contained both iron oxide and aluminum-impregnated cellulose acetate butyrate (CAB). These components are potentially reactive, even after fully setting. In fact, iron oxide and aluminum are sometimes used as components of solid rocket fuel or thermite. The propellant for the Space Shuttle solid rocket booster includes aluminum (fuel, 16%), (and) iron oxide (a catalyst, 0.4%)."

I have seen a test done a small piece of fabric that has been saved from the Hindenburg: it burned like a ping pong ball. S srrrooooof !
There is also all kind of other theories including sabotage but I really think
the type of paint covering plus the thunder storm that was very close was the perfect recipe for that to happen.

Now back to hydrogen: The Hindenburg would have been filled with any combustible gaz and it would have burn to the ground anyways.
Hydrogen is not an explosive it needs oxygen to burn.
Or the hydrogen was leaking and got ignited by a spark, lightning, St-Elmo fire, engines ignition system or the paint on the fabric was strike by lightnig and then ignited therefore letting the hydrogen to leak and mix with the ambient air.

Basically hydrogen is scary because it is a combustible gas that is easy to ignite and it diffuses rapidly due to its low density. Besides of that it is as dangerous as any other gas.

What happened really ,we probably will never know.
But for sure this incident put a term to the vocation of those very nice flying
cigars. Too bad they ended up in smoke !

Cheers,

[beto9]

Have you ever burned steel wool?

Try it. Get the fine variety, put a match to it and watch it burn.
Fast oxidation, as I remember reading...

So, who is going to invent the steel wool O.S. engine? I cannot imagine the tank and the fuel feeding mechanism... Would it provoke interference?
Should it have rubber gaskets?

[Sunfly]

'Ve been there done that. I was probably 14 years old.

I was very dangerous back then... and may be still today ..stay away from me.:D:D:D

After playing with a paint gun with the paint replaced by gaz.
This was like a big furnace burner.What a rush !

I stopped all my experiments when my pulso-reactor leaked a good 6 ounces of naptha on the wooden platform near my father's workbench and the big splash of fire was spreading rapidly.
It was about 12 inches in diameter when I held my breath and
decided to use the bucket of water I prepared before playing with my experiment.
I got lucky.
I took the bucket and rushed the fire out.

No more playing with fire besides my slow burn stove... no more :D

[Sunfly]

Oh ! By the way if you would be there around a bon fire with me at night be on your gards. I may throw a can of gaz and tell you to run.
No matter what, if I say run, just run and don't ask me why 3 times. :D:D:D

[Eric Marchand]

I've read that what brought down the hindenburg was a combination of very small leaks at the seams which were not considered an issue, and static electricity. The airship would devellop a charge during flight, like a ballon rubbed against your head (for those of you with hair). When the wet anchor lines touched the ground, small sparks jumped the skin seams during the discharge and ignited the small leaks, which in turn ignited the skin itself.

It's a thoery, but recreations have proven the likelyhood.

http://www.geocities.com/hydrogenpower1/essays/hindenburg.html

[Eric Marchand]

But going back to the original issue, before the threadpolice intervene...

Coleman fuel in gas engines : Good or Bad ?

[zorba]

Either way it wont hurt the engine. You still have to mix though.

If you go to RR you will see that the only advantage for Coleman over gasoline is the smell. Coleman burns clean.

If your engine is required reg octane then you can use Coleman which is 55 octane and if you require higher octane gasoline then you go with 91 or 93 octane gasoline. DON'T mix the two. A guy did this and he put the leftover fuel in his lawnmower. The thing will not shut off till it run out of fuel.

Is all up to you.

The only difference is that if you have a stock engine then you can switch. But if your engine is been machined by Hanson of B.H Hanson then the warranty is void but from Al of Toxic Racing Machines he don't mind.


Which is cheaper Gasoline or Coleman fuel?
You go with the cheapest of course.


Cheers