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80% Gasoline + 20% Kerosene = 20% more power?

  1. Jan 29, 2015 #1
    I did an experementing mixing 10%, 20%, 30% and 25% kerosene with gasoline that contains 10% alcohol.

    10% kerosene + 90% gasoline the lawn mower engine starts easy and runs very good.

    20% kerosene + 80% gasoline the lawn mower engine starts easy and runs very good.

    30% kerosene + 70% gasoline the lawn mower engine is very hard to start and will almost will not run.

    25% kerosene + 75% gasoline the lawn mower engine it a little hard to start and runs a little ruff.

    With 20% kerosene the lawn mower cuts down tall grass like nothing. It cuts right through grass it can not cut with just gasoline alone.

    I took my 1999 Chevy tahoe out on the highway to see how quick it will pick up speed from 0 to 60 mph. I returned home, removed drain plug on fuel tank then put a mix of 20%/80% kerosene/gasoline in the tank. Did another highway test 0 to 60 mph 20% faster.

    It typically takes a full tank of gasoline to mow my front yard but with 20% kerosene I ran out of gas after mowing about 80% of the front yard.

    Next I did a mileage test on my 1999 Chevy tahoe. I always text gas mileage when I fill up because I have learned not all gas is equal, so I have learned from expereience that a certain gas stations gives me much better gas mileage that others. I buy my gas at that certain station that always give me about 300 miles on a full tank of gas.

    Using the best gas that gives me the best mileage 300 miles per tank I added 20% kerosene to do a mileage test. I got 240 miles on a tank of gas. The engine is burning about 20% more fuel and giving me about 20% more power.

    I have only taken 1 year of high school chemistry and 1 semister of college chemistry.

    I would like to understand why 20% kerosene and 80% gasoline that contains 10% alcohol makes the engine burn 20% more fuel and produce 20% more power?????
  2. jcsd
  3. Jan 29, 2015 #2


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    Burning 20% more fuel to get 20% more power, what's so great about that? Now, if you burned 20% less fuel and got 20% more power, then you'd be on to something.
  4. Jan 29, 2015 #3
    The thing that is interesting to me is NO change was made to the carburetor. With no change the orifice hole is still metering the same volume of fuel.

    Mixing gasoline with kerosene must be like mixing gravel with sand.

    The engine is still sucking in the same volume of AIR as before. It seems to me the engine should need more air to burn more fuel.

    gasoline = C8H18

    Ethanol alcohol = C2H6O

    kerosene = C12H26
    Last edited: Jan 29, 2015
  5. Jan 29, 2015 #4


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    Not exactly. Amount of fuel going through the orifice depends on some combination of the density, viscosity and surface tension. None of these was kept constant.
  6. Jan 29, 2015 #5


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    Given that kerosene is already a component of gasoline, I don't think so.
    From what I've scoured in the past, gasoline hydrocarbons run from 4 to 12 carbon atoms per molecule. C8H18 is merely the average.
    A couple of sources stated that there are 500 different compounds in gasoline.

    The following wiki entry is a bit before my time, and they list no reference, but it seems legitimate:

    Googling "TVO", I found the following, which makes it again sound like you're not mixing sand with rocks:

    and it continues:

    It appears, that you may be breaking the law, with your experiments.

    Unfortunately, I'm not a lawyer, and can't find the appropriate code, and can only present the following, as evidence:

    It might be listed under the "Al Capone" clause: "You can kill all the people you want, but if you fail to pay your taxes, you're going to jail".
  7. Jan 29, 2015 #6


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    If you use off-road fuel in your road vehicle, which fuel does not have any road taxes assessed at point of sale, you can always keep a record of the amount of fuel used and pay the taxes later, if you are conscientious. ;)

    There's no big mystery about burning diesel in a gas engine. I knew a guy once who drove a Ford LTD. He apparently got distracted once when filling up, and put in a tank of diesel instead of gasoline. He drove away from the pump and didn't notice anything until the remaining gas in the tank was consumed. A big cloud of smoke started to come out of the tailpipe. Since the carburetor was adjusted to burn gasoline instead of kerosene, the proper air-fuel mixture was not being fed into the engine, and a lot of unburned soot was coming out the back of the car. He took his car to a mechanic, where the fuel mix-up was discovered. The car reportedly survived this mishap and ran well once the proper fuel was used. The excess diesel was a bit hard on the oil in the engine, however.
  8. Jan 29, 2015 #7
    LOL There is a do gooder on every forum that does their best to twist things into something illegal. What is that about? Why are some people so negative minded. I am running kerosene in my hoddy jet engine not my vehicle. I discovered this works by experementing with my lawn mower. Next I tested the mix in my vehicle just to prove it works in all 3 engines and to determine exactly how much kerosene can be mixed with gas and still run. I barely remember from chemistry class, there is a way to add up all the carbon, hydrogen and oxygen in these 3 fuels but I dont know how it is done. I am not sure why gas and kerosene mix to produce a fuel that produces more power with the same amount of air. One more experement I need to perform is mix 2 cups of kerosene by volume with 8 cups of gasoline by volume to see if that equals 8 or 10 cups total or something in between. I recall from chemistry class you can mix 1 cup of chemical A with 1 cup of chemical B and you get 1 cup of chemical C. When small molecules mix with large molecules the small molecules fill in all the empty space in the large molecules like mixing 1 cup sand with 1 cup gravel. I know there is a scientific way to do the math to calculate the exact % of kerosene to mix with the exact % of gas to get maximum power for an engine. I think I am on the wrong foums no one here seems to have a clue about chemistry.




    Last edited: Jan 29, 2015
  9. Jan 29, 2015 #8


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    Kerosene is 11% denser than gasoline, so more of it will go through an orifice than gasoline, but has 4% lower energy density. So a net increase of 7% power delivered per unit volume.

    A bigger problem is using propane in a dryer made for natural gas, without changing the orifice...
  10. Jan 29, 2015 #9
    Thanks Russ it has been 40 years since I took chemistry in college I had forgotten to consider fuel density. I have forgotten how to add up atoms. There is a lot of hydrogen in this fuel. Hydrogen is an interesting fuel it will burn with a very wide range of oxygen but it has low mass. I think I will understand more about how the pulse jet engine runs if I could learn more about the fuel.

    It is very interesting to start the engine on propane, switch over to gasoline, then switch to gas/kerosene mix, then switch to alcohol. Each time fuel is switched thrust increases and there is a very noticable increase in how loud the engine sounds. Each fuel is noticable hotter. Even though gas burns slightly hotter than alcohol the engine burns about 40% more alcohol than gas and power takes a big increase and the engine burns so hot the metal looks transparent. Even with 5% water in 95% alcohol power is way higher than any other fuel. Mass flow is the key to thrust. I wish I could remember my chemistry.

    A friend from Germany keeps telling me to run my engine on Benzine but i have not even cosidered that fuel yet. I need to relearn my chemistry first.
    Last edited: Jan 29, 2015
  11. Jan 29, 2015 #10


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    Propane has fewer carbon and hydrogen atoms than gasoline or kerosene, so it is not surprising that you get more energy from the latter fuels. Liquid fuels, because they are also denser, are able to deliver more energy per unit volume.

    You should be careful here. 'Benzin' is what the Germans call gasoline, and what the British call 'Petrol'.

    'Benzene' is a dangerous chemical which is known to cause cancer in those who handle it.

    While you are re-learning your chemistry, take some time and re-learn how to safely handle these substances.
  12. Jan 30, 2015 #11


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    To be honest, there is not much chemistry in mixing fuels - there are no reactions, just mixing. As it was already stated in the thread, each of the fuels mentioned is already a mixture of many different hydrocarbons, mixing different fuels mostly changes hydrocarbons proportions. There is much more chemistry in the burning, but in general every compound burns separately. You can try to calculate burning stoichiometry/energy output of the mixture starting with the average number of carbons in "an average gas compound", but these are only approximations. You will probably get comparably accurate results from the linear combination of the fuel parameters, with much less hassle.
  13. Jan 30, 2015 #12
    Fuel Mass Flow, heat and expanding gas determine thrust of a jet engine and rocket engine. If the fuel is used to cool the engine the heat the fuel picks up and sends back through the engine increases the thrust. Mass flow is very important it increases thrust too. Too much heat is early death of the engine, low carbon fuel is best.

    The German V2 Rocket used Liquid Oxygen + 75% alcohol with 25% water. Water is high mass and expands 1800 times its volume when it turns to steam.

    I spent several hours trying to find high mass flow fuels. The number are not all the same that is driving me nuts. Some are, cm3, some are ft3, some are m3, some are things I dont know. I can convert cu meter to cu ft but dont know how to conver the others. Some places tell me mass, some places tell me density, some places tell be both.

    So far Methanol is the best choice as far as I can tell C H4 0. One carbor for 4 hydrogen is good plus 1 oxygen means the engine can burn a lot of extra fuel. Density is .7925. I know the engine will run good with small amounts of water like 1% and 2% but I dont know how to calculate maximum water for maximum thrust without running the engine over and over trial and error to see what works best. If I know how to do the chemistry math it would save me a ton of work.

    Hydrogen is a very interesting fuel it will burn in a very wide range of air mixtures from about 3% to 15%. Hydrogen maximum temperature in air is 2000 degrees.

    Methanol density = 32.04 g mol -1 what ever mol-1 means? I dont know how to convert this to lb/cu ft.

    Gasoline density = 44.9 lb/cu ft

    Kerosene density = 49.9 lb/cu ft

    #1 Diesel density = 54.5 lb/cu ft

    I am pretty sure these hydro carbon fuels contain no oxygen like alcohol. The only reason I can determine why gas/kerosene mix produces more thrust than gasoline alone is density of kerosene is 5.0 lb/cu ft higher than gasoline. The engine has NO air adjustment so apparently it does not take any extra oxygen to burn this fuel mixture. Diesel density is 9.6 lb.cu ft more than gasoline.

    Next question is, will a mix of 80% Methanol / 20% Diesel produce more thrust than 100% Methanol?

    Some of the hobby guys add propylene oxide to gasoline to get more thrust. Propylene oxide is C3 H6 0 with a density of .83 g/cm3 not sure how to convert that to lb.cu ft? This stuff has an oxygen molecule just like Methanol.
  14. Jan 31, 2015 #13


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    Just because there is an oxygen in the formula doesn't mean it will burn better. In most cases it means the molecule is already partially oxidized, which is equivalent of saying part of its energy was already used.

    This is not density, this is molar mass.

    Even if they did, it wouldn't mean much, see above.

    No, it is not like in methanol. This is a strained molecule, which means it contains some additional energy.

    Unit conversion primer: http://www.chem.tamu.edu/class/fyp/mathrev/mr-da.html
  15. Feb 1, 2015 #14
    I tried to test run my pulse jet engine today with 80% methanol and 20% diesel but as it turns out diesel will not mix with methanol. Kerosene will not mix with methanol either. It is like trying to mix oil with water.

    Today tried to determine the real run frequency of the pulse jet engine. The engine length is 19" long. Using the formula to calculate the frequency of a closed tube i get, 1200 degrees F = 376 Hz, 1300 degrees F = 394 Hz, 1400 degrees F = 411 Hz.

    The engine runs red hot we know for sure the engine is hotter than 1100 degrees because metal glows a very dull red hot at that temperature.

    The frequency detector says the REAL frequency of the engine is 298 Hz to 303 Hz.

    Doing the math the only way I can get 300 Hz the engine temperature has to be 763 degrees F. The only way to explain this is the engine sucks in 70 degree air 300 times per second if the engine is running at 1456 degrees F then 763 is the average temperature.

    How is it possible for the engine to run so hot it glows extremely bright red when the average temperature is 763 degrees F.

  16. Feb 1, 2015 #15
    Hello pf. Interesting thread. In the earlier posts there was some ambiguity. Can someone please advise, is kerosene the same thing as diesel ?

    BTW, I once accidentally half filled my gasoline tank with diesel. Didn't notice any difference except that the motor seemed to make a little more noise.
  17. Feb 1, 2015 #16


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    What formula did you use?
    Show your working (with all units) and we can go from there.
  18. Feb 2, 2015 #17
  19. Feb 3, 2015 #18
  20. Feb 3, 2015 #19
    I'm having a bit of trouble believing the LTD anecdote: kerosene/diesel has the equivalent of a very low octane rating, since it is manufactured to explode just from the pressure and warmth of the piston's compression. Putting diesel in gasoline-engined car should result in unbelievable knocking -- as though the engine timing were way out of kilter, because the fuel will be exploding well below wherever the normal engine timing says it should (number of degrees before or after TDC). I can't imagine (a) not noticing anything and (b) not actually damaging the piston ends.

    Can someone who knows about engine technology comment on this?
  21. Feb 3, 2015 #20


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    IDK how much gasoline was in my friend's car when he filled up with diesel. If there was an appreciable amount of gasoline in the tank, the octane number of the mixture, although lower, might still have been palatable to a low-compression engine. IIRC, he didn't drive the car for very long before the mix up in fuel became apparent.

    In any event, the focus of the OP seems to have shifted from burning his mixed fuel in an auto engine to making some sort of ramjet.
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