Ethanol avoidance

Discussion in 'Powerboats' started by tom28571, Sep 27, 2009.

  1. powerabout
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    powerabout Senior Member

    U4ea32
    You say cheaper ok but almost every analysis I see shows it carbon negative versus gas given all the extra burnt trying to produce it.

    Even in OZ where they are using the molasses left over from the sugar production, there is no business case for it without government grants, hence the alcohol producers are the biggest contribitors to the current goverenment re donations...you wouldnt need to do that if you had a good business would you?
     
  2. FAST FRED
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    FAST FRED Senior Member

    10% alcohol , if removed will return the gas to the octane , with out the alky.

    For boats using gasahol the problem frequently is not octane ,
    the carb system flows a certain GPH of fuel to a certain volume of air.

    The alcohol takes up room in the fuel flow , but unless much larger jets are installed the mixture will have to run lean at WOT.

    Perhaps this is the reason for melted pistons , not detonation.

    Folks worried about lead fouling with 100LL can use Alcor TCP lead scavenger (hard to find) or Decalin from Aircraft Spruce and Specialty, $27.40 + $10 shipping . A quart will doctor 640 gallons.


    FF
     
  3. TollyWally
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    TollyWally Senior Member

    I remain rather skeptical of any negative effects of carbon production but I am interested in the caloric inputs neccessary to grow and distill fuel.
     
  4. CDK
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    CDK retired engineer

    That question is hard to answer Fred.

    Alcohol is C2H5OH, fossile fuel is a mixture of CH4, C2H6, C3H8, C4H10, C5H12 and so on.
    For a fixed amount of mixed fuel, the caloric value decreases if more ethanol is added. The difference is not very impressive, but it is there.

    To burn C2H5OH, you need 3 O2 to make 2 CO2 and 2 H2O, the 3rd H2O is formed with the O already present. To burn a hydrocarbon like C2H6, you need 3.5 O2 to make 2 CO2 and 3 H2O, so if the air/fuel ratio is correct for hydrocarbons, the presence of ethanol will make it lean. And we do know that a lean mixture increases the combustion temperature.

    But that knowledge applies to hydrocarbons only. If we add ethanol, the caloric value is reduced, so the combustion temperature should be a fraction lower.....
     
  5. powerabout
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    powerabout Senior Member

    I would agree with that Fred, you need to burn more alcohol so an engine jetted for gas/petrol will be lean when using a mix and that can be instant death for a 2 stroke especially an older one with higher compression.
     
  6. TollyWally
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    TollyWally Senior Member

    The drag racing boys burn alcohol because it runs cooler. This allows them to avoid detonation and run higher compression. They also run larger jets. The larger jets thing seems to tie in with CDK's point about ethanol needing different air/fuel ratios to avoid a lean condition.
     
  7. powerabout
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    powerabout Senior Member

    Sure does Tolly
    I remember guys racing Merc V6 outboards on methanol in OZ, they removed the main jets and it just ran through the threaded hole so they used plenty.
     
  8. Boston

    Boston Previous Member


    I dont like ethanol
    it takes about 250 to 350 lbs of corn to produce an average automobile tank of ethanol
    at 10% ok thats ten tanks of gasahol
    but its still what it would take to feed one adult for one year
    its a bad idea all around
    but
    your complaints are not all that sound
    a thirty year old Evenrude with a gummed up carb
    c mon that thing is ancient and bound to have a screwed up something regardless of fuel
    did you drain it and run it dry after each use
    small motor
    takes a little more care to keep it ship shape

    Stihl chain say
    serves you right
    buy a Husky next time
    and run it dry after each use like they tell you to do

    yamacowasucki 50
    again would have solved the problem to simply run it out of fuel after each use

    all problems could have been solved with out spending a dime had you been on it

    as it is your blaming alcohol for a maintenance issue

    stuff eats rubber
    rubber gum's **** up
    run the engine dry after each use and you should be fine
    that way the alcohol doesn't sit and make sludge out to the rubber components

    one thing that is news to me is that it seems your suggesting that they are putting alcohol into diesel

    Ill have to look into that one as Ive not heard it before

    so in conclusion
    don't let fuel sit in small engines
    screws em up and glazes ****
    alcohol or no

    don't buy crap chain saws

    and a thirty year old Evenrude is bound to need a rebuild

    that and some skinny ******* in Africa will thank you for not making one tank of fuel out of enough food to feed his sorry *** for a year

    oh
    and it does seriously effect mileage
    for the worse
    stuff has 1/3 less btu value per gallon
    and it burns at a different stage of the stroke
    so its a wash in an engine designed to run gas
    that's why you loose the percentage dilution
    its not igniting at the right time
    I think
    not positive about that but my old neighbor used to race indi cars and they run on alcohol so yell at him if I got it back wards or anything

    cheers
    B
     
  9. powerabout
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    powerabout Senior Member

    And if you have a fuel injected stern drive or outboard which all have dead end ( no return line) fuel systems, it rusts away stuff as the water cant get out of the system
     
  10. Boston

    Boston Previous Member

    now that was a viable *****

    that **** sucks moisture out of the air and needs to be in an air tight container at all times or it gets wet
    the additive Tom is probably talking about is likely something that addresses that issue
     
  11. Frosty

    Frosty Previous Member

    Standing in the supermarket the other day was gallon cans of palm oil stacked higher than 2 men.

    It worked out marginally more than B5 deisel that I normally use , had it not I would have been tempted to fill the truck with it.

    33 degrees every day in the shade should not present a problem.

    Perhaps bung in a pint of petrol per tank for a bit of kick on starting.
     
  12. Boston

    Boston Previous Member

    palm oil is fast becoming the largest contributor to deforestation in the tropics
    I avoid palm oil as often as possible
    even here its in about 10% of all grocery products
    they even put it in milk

    B
     
  13. Frosty

    Frosty Previous Member

    Nice to know our governments have our best interests at heart is'nt it?

    I love "potato chips" as you call them but if I think Palm oil as I buy them I can usually put them back on the shelf.
     
  14. TollyWally
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    TollyWally Senior Member

    Boston,
    Most of your post is a little off base. You are missing the forest because of the trees. While ethanol has many downsides the single largest one in older equipment is the solvent action. Dissolving accumulations of otherwise stable residue in fuel tanks and running it through the fuel system is the biggest problem, not running Swedish chainsaws vs German ones or the age of your Evinrude.
     

  15. powerabout
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    powerabout Senior Member

    Tolly good point, its a solvent causing big problems...

    Especially as in the US they always had crap in the fuel forming varnish.
    We were always told about this during training ( Merc/OMC) but its unheard of in Australia
    Take an engine that has been left for 5 years and the carb is as clean as the day it was made....
    of course that will now change as there is ethanol in OZ now
     
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