Does gasoline really burn off of oil?

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I thought once oil gets diluted with gas, its very difficult to get rid of gas, even if you drive for hours it would not evaporate out?
 
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I thought once oil gets diluted with gas, its very difficult to get rid of gas, even if you drive for hours it would not evaporate out?


As I understand it there are volatile compounds that evaporate or whatever the scientific term is at a certain temperature. Then you have compounds that remain
 
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Gasoline (and ethanol) will evaporate more quickly with heat, but fuel always has some additives and it's those additives in the crankcase that have me wondering... do they stay in the oil or do they also evaporate? Are the fuel additives by their chemistry/nature not considered a problem when in motor oil? Is there even enough concentration of fuel additives to be concerned, depending on the amount of fuel dilution ?
 
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Gasoline (and ethanol) will evaporate more quickly with heat, but fuel always has some additives and it's those additives in the crankcase that have me wondering... do they stay in the oil or do they also evaporate? Are the fuel additives by their chemistry/nature not considered a problem when in motor oil? Is there even enough concentration of fuel additives to be concerned, depending on the amount of fuel dilution ?


Well, I guess if your oil level raises because of fuel dilution in GDI due to short cold trips, is it possible for oil level to go down close to original level if you say take a two hour long trip?
 
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There is a lot going on in the crankcase that helps gasoline components flash off. Heat, agitation exposing more oil surface area to the…vacuum in the crankcase. Much of the time the crankcase is under vacuum, which lowers the flashpoint of the liquids inside. The volatile components are soon gone with any significant run time. i Consider an hour or greater at highway speeds to be significant operational temperature time. I often have 3-8 hour legs so I do not worry much.other than checking oil level every 1k.
 
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Only slight vacuum. How is flash point relevant?
Flash point is the temperature where vapors are being emitted from a liquid. Even a slight drop in atmospheric pressure drops the flashpoint. What this means is that there is Fuel vapor being pulled back into the intake even at lower oil temperatures As it flashes out of the engine oil.
now there are remnant and heavier fractions left behind. Once you start new engine with new engine oil in it you will never again have pure engine oil in the crankcase Unless it is torn down and shines new again.there will always be fuel fractions..even after a fresh oil change. fortunately dispersant and detergent packages to a good job of spreading them out And keeping oxidized Bits from sticking.
 
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Flash point is the temperature where vapors are being emitted from a liquid. Even a slight drop in atmospheric pressure drops the flashpoint. What this means is that there is Fuel vapor being pulled back into the intake even at lower oil temperatures As it flashes out of the engine oil.
Flash point is the lowest temperature the vapors of a flammable compound will ignite when an ignition source is introduced. Vapor pressure is the correct term for what is being discussed.

Ed
 
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What happens to the quality of the oil , after it is diluted to say 3-5 % then is boiled off?

Used to get a lot more acid forMarion from gasoline in oil, but gasoline now is lower in sulfur. the main issue is there
Flash point is the lowest temperature the vapors of a flammable compound will ignite when an ignition source is introduced. Vapor pressure is the correct term for what is being discussed.

Ed
You are correct. I looked it up last night but Went down the rabbit hole of equilibrium and fell asleep.
 
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Used to get a lot more acid forMarion from gasoline in oil, but gasoline now is lower in sulfur. the main issue is there
And actually you don’t get acid formation directly from the sulfur compounds in the gasoline, acid comes from the sulfur oxides and water after combustion.
 
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