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Simple question: Does gasoline rust metal?

  1. Jul 16, 2008 #1
    If yes how about in comparison to water? I ask cause I was wondering how they stop the metallic fuel injection tubes from rusting out. Is there a coating or does it just not rust in presence of gasoline?

    Im assuming that gasoline doesnt rust since its a hydrocarbon and water contains O, and rusting is the product of oxidation. Is this correct?
    Last edited: Jul 16, 2008
  2. jcsd
  3. Jul 16, 2008 #2
    Well, I'm not sure, but keep in mind that gas tanks in automobiles, for example, often have a substantial area above the gasoline that common air sits.
    Through condensation and other factors, the water and oxygen(and other gases) in that air is mixed to some degree with the gasoline.
  4. Jul 17, 2008 #3
    Your question is not as simple as you think. "Rust" is a generic term for oxidation that generally refers to Iron Oxide. The same sort of oxidation reaction can occur with other metals. Water doesn't cause rust, but it's presence does facilitate the process of rust formation on Iron. I doubt that automotive fuel lines are made of Iron, or even of mild steel, for that matter. As for steel gasoline tanks; examine a very old one and you will discover that they do, indeed rust.
  5. Jul 18, 2008 #4
    a metal cannot "rust" without oxygen. but i can corrode..im guessing there is a coating on the inside of the tube.
  6. Jul 25, 2008 #5
    After working with old cars for many years I have found that steel tanks don't rust (internally) unless they get water in them (which they all do) that is with conventional gasolines/petrols where the water and petrol do not mix, in this case the water sinks to the bottom of the tank and causes it to rust in that location. Newer ethanol based fuels dissolve the water in petrol and reduce the rusting effect.
  7. Aug 4, 2008 #6
    They'll rust, same as brake lines, from the inside out usually.
    Fuel rails that are on the engine, aluminum I personally have on my car, are simply that, aluminum. I am thinking about running E85 on this car, and also about this being an issue, they'd possibly have to be anodized inside.
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