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On SE:Aviation, someone asked why planes don't use gasoline.

A comment below stated following:

A better question is why do cars run on petrol rather than kerosene. – Aron

So, here I am asking the exact same thing.

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    But please do not put cerosine in a petrol car because the lubricity is definitely lower than normal. And in the worst case your canrod will break. – MightyV8Engine May 17 '17 at 20:01
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The primary reason is gasoline is more efficient. It vaporizes easily (below boiling point of water), burns faster and more completely. On top of that, it is cleaner burning than kerosene.

Kerosene is closer to diesel fuel and is less refined. It can withstand higher temperatures before it vaporizes. This means combustion is not as easy as it is with gasoline.

Reference; "What's the difference between gasoline, kerosene, diesel, etc?", 1 April 2000. HowStuffWorks.com

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    Something to realize is a car which can run on diesel can run on kerosene. Like you said, though, it isn't as refined as diesel is and therefore will have more pollutants and not be as efficient. Not that I would run a car on it, but if you were in a pinch, it can and has been done. – Pᴀᴜʟsᴛᴇʀ2 May 17 '17 at 18:45
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    @Pᴀᴜʟsᴛᴇʀ2 I wouldn't risk it on a modern diesel except in a true emergency in which I'd risk breaking the car. I have known people running old diesels (mechanically controlled) on paraffin/kerosene, as the easiest way to use it up. – Chris H May 18 '17 at 8:38
  • The injector pumps of modern common-rail injection car-diesels are very easily destroyed by fuel with insufficient lubricity (generated with fuel additives). I doubt you are risking such an engine running on kerosene, so much as guaranteeing severe damage. You'll probably also clog up the particulate filter, which is another expensive repair. – nigel222 May 18 '17 at 14:34
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Much of the reason is historic. Back when cars were new Gasoline was actually a by-product of kerosene production from petroleum. Kerosene was a much more valuable commodity at the time because it was widely used for lighting, so nobody wanted to use it for transportation. Gasoline was marketed as an auto fuel by the oil companies mainly to find a use for it, and it turned out to be a good choice because at the time the technology favored lighter fuels. Gasoline became popular, and that led gasoline overshadowing kerosene as the primary use of oil. Thermal cracking was developed to produce more gasoline from crude oil, enabling the automobile industry to keep expanding.

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    "reciprocating engines work better with lighter fuels." That's just marketing disinformation. What it really means is "reciprocating engines designed for lighter fuels don't run on heavier fuels" - which is a completely different statement. If the statement was true, why on earth are more than 50% of European cars diesel-powered? (Hint - the answer isn't "because American car manufacturers are smart but Europeans are stupid!) – alephzero May 17 '17 at 19:26
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    Diesel isn't kerosene @alephzero. – GdD May 17 '17 at 20:02
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    @alephzero You are very wrong on the diesel front. Diesel has much more energy density than gasoline. To ignite properly, you need to compress more air into the fuel mix, so diesel engines have higher compression. However, higher compression requires heavier, larger, more robust components. Having to design around these constraints is why for a passenger vehicle, a similarly sized diesel engine can generate a lot more torque, but sustain a lower continuous rpm, and makes lower horsepower since it requires a lot more energy to accelerate those parts. – iheanyi May 17 '17 at 23:20
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    @alephzero Early car tech favored fuels like gasoline, because they allowed relatively small and lightweight engines with usable rpm output. Today, gasoline still has that advantage - with the push for more fuel efficient, less polluting, light weight vehicles, gasoline fueled wins out. As hybrids gain popularity, diesel will continue to decline since electric motors can more than compete on the torque front. The rise of turbocharged diesel engines has helped (reducing compression stroke length required so allowing for more rpms and HP), but I don't see it being a diesel savior. – iheanyi May 17 '17 at 23:23
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    The scientific jury is out as to whether the particulates from Diesel are worse than CO2, there is evidence that suggests ice sheet loss may be due more to them turning grey from dust and absorbing more heat than the temperature of the surrounding air. Getting off-topic though. – GdD May 18 '17 at 11:13
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Engines can run on Kerosene,But cold starting is a problem, as vaporisation is not as good (I have used it many times in Landrovers on the farm). Furguson tractors used Petrol for warm up then switched to Kerosene with no ill affects. However due to the poorer vaporisation, timing must be altered and performance is reduced

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The reason is diesel can burn after compression or alone. This feature is absent in the case of kerosene. So, this is the best possible reason of not using kerosene as a fuel. Lubricity is definitely lower, as is energy value (especially in summer).

But:

It would work fine in diesel, if 2-stroke oil is added to get the lubricity up.

  • Some sports airplanes can be ordered with either gasoline (140 octane!) engine or with a diesel engine. According to the manufacturer the diesel variant works with "pure diesel, pure airplane kerosene (used in jet airplanes) or any mixture of both". – Martin Rosenau May 18 '17 at 12:19
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Engines (and jet turbines respectively) have been optimized for a fuel (gasoline, diesel or kerosene respectively) and vice versa. If turbines ran better on a "slightly different" kerosene then kerosene would be produced "slightly different". If turbines could be build to run better with the available kerosene, the changes would be introduced (assuming they are technical/economical viable).

So cars run on their respective fuels, because kerosene is a bad choice for their types of engines. And the types of engines are good choices for the size/weight/power/price/... requirements of a car. You could build a turbine powered car and fuel it with kerosene. The result is something like this:

https://en.wikipedia.org/wiki/ThrustSSC

You could set a speed record, but don't even think about trying to park (let alone drive) it in the city...

P.S.: I noticed, jet engines on cars are "more widely" spread than I'm implying above: https://en.wikipedia.org/wiki/Jet_car

  • I tried adding the picture from the article but it keeps saying "format not supported". – NoAnswer May 18 '17 at 14:29
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Here were I live some people do run their petrol/gas cars with kerosene; their engines are old ones tho, American cars from the 50's and soviet Ladas and Moskvich from the 60's. What they do is to pre-heat the kerosene before entering the engine, an artifact between the carburetor and the intake manifold. When the kerosene goes through it, it get vaporized and then the engine can run. They also need to change the timing. These cars works "fairly enough" well with kerosene, you can smell them differently, and they just run...however their power and pickup get very affected negatively.

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