Ethanol-proofing a gas tank

Discussion in 'The Garage' started by Luke, Sep 3, 2010.

  1. urbanXJ

    urbanXJ Long timer

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    just thinking out loud here, but if that works, then we can seperate the ethanol ourselves, all is needed is a sepratory funnel
    #41
  2. Luke

    Luke GPoET&P

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    Hey Motojunky;

    Sorry your tank didn't turn out; it sounds like we both applied it the same way, so whatever the difference is between this stuff working and not working must be small.
    #42
  3. motojunky

    motojunky Professional Idiot

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    Weird, isn't it?

    I couldn't have been more particular about prep/following instructions/etc. so I really don't even have a guess as to why it worked for you and not me. I'm just "lucky" like that, I guess. :(:
    #43
  4. motojunky

    motojunky Professional Idiot

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    I took a look at the inside of my Scorpa tank and found that the blisters have not grown or changed in appearance since the last update. I have also not had ethanol fuel in the tank in that time. I've had the Caswell in the tank for about a year and a half now. My suspicion is that even though I prepped with extreme care and overkill, the Caswell did not adhere well in those spots. I suspect that I could run ethanol tainted fuel now without damaging the tank. The coating is intact, it has just lifted from the inside of the tank in the blister areas.

    If I were to do it again, I would repeat the preparation instructions several times over the course of a few days to make sure to remove any possible contaminant. At this point, my tank is fine and I've decided that given the cost (if even available?) of a new tank, I'm going to leave it alone. I'm also sticking with VP C9 at $12/gallon. Painful, but really not a big deal given the small amount of fuel the bike uses. It's interesting to me that C9 (unleaded, 96 octane) is a few dollars cheaper than SEF94 (unleaded, 94 octane). Best I can tell, it's a marketing thing.
    #44
  5. troidus

    troidus Long timer

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    Clean sand might have been better than screws for roughing up the surface.
    #45
  6. motojunky

    motojunky Professional Idiot

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    :norton
    The tank has many oddly shaped small recesses. Seems like it would be nearly impossible to get all of the sand out. Of course those same recesses are hard for the screws to get to as well. The problem areas are pretty "accessible" though. Dunno - I stopped worrying about it a long time ago. :D
    #46
  7. *kartman*

    *kartman* GO Bacon GO !

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    Hey guys,

    I'd like (I must) seal the tanks of my Rally KTM in order to prevent the outer coat from blistering. Should be the right stuff for the job, right ? As it stops gas fumes from "moving" through the XPE plastic ?

    Luke, as you have done it I have a short question:
    Will the hardened Caswell remain a bit flexible ?
    A rally bike is prone for crashes and I don't want the seal to become cracks or even fall of from the surface...

    Best, Martin
    #47
  8. Luke

    Luke GPoET&P

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    As long as it bonds to XPE you should be good. I'll take a look at the tank tomorrow and see how it's held up.
    #48
    *kartman* likes this.
  9. Luke

    Luke GPoET&P

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    I just checked. It doesn't feel soft, it feels like regular epoxy. So I'd expect it to have the same resiliance as the fiberglass, but less then any sort of dirt bike plastics. Mine has held up, but the tank is tucked out of the way and hasn't taken any big hits.
    #49