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mlts22's avatar
mlts22
Explorer II
Aug 08, 2013

E85 in generator?

One of the people I met while camping out and keep in contact with apparently uses E-85 and E-100 in both his inboard Onan generator, and his Hondas. He learned this while on a trip to Brazil where ethanol is relatively cheap.

The Onan, he moves the altitude switch up a bit. The Hondas, are slightly choked. This makes the mixture slightly richer, to compensate for the less energy per spray in ethanol.

This is the first time I've heard about this, and I checked the manuals of both models, and E-85 is a definite no-no. However, this acquaintance of mine swears by it, with the caveat of always draining the gas completely in the Hondas, and squirting Sta-Bil in the tank of his MH to keep the water from settling out and hydrolocking the generator.

Has anyone even heard of this? I personally would not want to risk anything not expressly designed for booze mainly because of the corrosion aspect of ethanol and the fact that E-100 is really E-95, with 5% water in it.

16 Replies

  • mlts22 wrote:

    The Onan, he moves the altitude switch up a bit. The Hondas, are slightly choked. This makes the mixture slightly richer, to compensate for the less energy per spray in ethanol.


    The choking has nothing to do with less energy. It due to the fact that the proper stoichiometric ratio for gasoline is 14:7 to one, while ethanol is 9:1.

    As others have said, the problem with using ehtanol in an engine that is not designed for it is the fact that the fuel lines, rubber parts, etc. will be damaged.
  • I wouldn't want to risk it ($2000 for a generator isn't cheap), but it seems that some people are having good luck with running it. I just wonder how common it is to convert a gas engine to run on E85/E100, as this is the first time I've heard about this.
  • Matt_Colie wrote:
    ..... You do know that Brazil is going away from ethanol as motor fuel don't you. ...
    Matt


    Really? That is certainly news, since they are still deep in their flex-fuel program and expanding ethanol production.

    Bloomberg report from July 2013
  • One of the problems with ethanol is that it will eat gaskets, plastics and rubber parts not designed for ethanol use. It will also pit some metals. Just use caution if you use it, could be a big repair bill to replace damaged parts.
  • I'd really like to hear from your friend in a few years. With the trouble that E-10 has caused me, I really don't think E-85 or 100 could be much worse. You do know that Brazil is going away from ethanol as motor fuel don't you. Sure, it can be made to work, but it has a whole new and different set of issues.

    Matt
  • I'm sure that the mfgr's don't want to worry about the problems that are associated with the ethanol products....so they strongly suggest that you not use them.
    That said, will they work....yes.
    Will they last as long as the engines not using the E-85....probably not! Or at the very least, will probably require additional maintenance, which may actually offset any monetary gains from the lower priced fuels. Some of those parts are pretty expensive!!

    StaBil does make an ethanol mix, which may be helpful....I've never tried it.

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