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Brake fluid in the gas tank

Yep. she did. my wife accidentally put a bottle of brake fluid in the gas tank of our chrysler T&C. the tank was full and a mechanic at the garage said to go ahead and drive it. so far, it drove.... should i be worried?


  • edited March 2009
    I have got to go with the mechanic as I know no better, I am not sure of what type of brake fluid put in, the probability it was ethylene glycol based, and I would do a treatment of sea foam now and after just for kicks.
  • edited March 2009
    I guess one question is does brake fluid dissolve in gasoline? I don't know, I know it does in water. If it does NOT dissolve in gasoline, then you have a big problem. I'd go buy a bottle of whatever brake fluid she put in, get a glass, and mix a little of it with some gasoline. If they mix completely, then at least your engine won't stall when a big slug of brake fluid makes it to the injectors...
  • edited March 2009
    I would just keep topping the gas tank up every couple of days. As in when it gets down a 1/4 of a tank or so top it off and dilute the tank.

    I had an old Dodge beater truck that would suck the brake master cylinder dry in a hard stop (bad power brake booster and leaky master cylinder I guess). The engine would knock and a nice white cloud of smoke would come out the tail pipe, but it ran that way for awhile before I scraped the whole truck.

    Reminds me of the story where i guy showed his wife how to check the oil and where to add it if needed. He forgot to show here the oil and she added washer fluid to the crankcase...

    EDIT: texases brings up a good point...I will have to play chemist on that one.
  • edited March 2009
    all i know is that it was the Gold Eagle brand. i couldn't tell you any specs on the product, the website has none. thanks for the reply
  • edited March 2009
    There are some materials that are miscible with water and gasoline, ethanol for example. "Glycol" brake fluid is not ethylene glycol, but polyalkylene glycol ether. I don't know what happens to it in gasoline, but Texases's suggestion of making your own observation is a good one.
  • edited March 2009
    got a new bottle as per Texases suggestion... played chemist,the brake fluid is clear and appeared to dissolve, but its sitting right now. i wanted to see if it separates while sitting.

    the bottle says it contains polyglycol ethers and inhibitor package... any idea if that material is miscible with gas? thanks again. dave
  • edited March 2009
    So you added brake fluid to some gasoline, and it resulted in a single clear liquid? Then I'd say it is 'miscible', and will be burnt gradually as you use your gas. If it were me, I'd follow the 'keep topping it off' advice above.
  • edited March 2009
    to clarify... the brake fluid was clear (I was hoping it was colored for better observation) it did seem to mix, though its pretty cloudy. i was glad to see it wasn't layered anyway. keep topping it off is tops on the list of to dos...
    i was also wondering about that sea foam treatment, do you think thats a good idea?
  • edited March 2009
    Hmm...if the brake fluid is clear, the gasoline is clear, but the mixture is cloudy, you could still have a problem. It may need time to settle. Cover the glass with plastic wrap and a rubber band and let it sit, then look at it (without shaking it).
  • edited March 2009
    sea foam can only help if it does anything at all. (I.e. it certainly won't hurt - and is a good thing to do once in a while anyway).
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