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Discussion Starter #1
since the yom kippur war, brazil has one of the best experiences with the use of ethanol as fuel in large scale, and even some compression-ignited engines were made to use ethanol and diesel fuels... instead of mix the fuels in the same tank as the regular flexfuel vehicles avaliable in brazilian and american markets, those engines had 2 fuel pumps and the fuels were kept in separated tanks... even after the '89-90 ethanol crisis in brazil, sugarcane farmers still use to convert their diesel tractors and trucks to run on their own ethanol... instead of scania's system that needs an ignition improver additive to get a proper ignition, in brazil the only concern was about the injection pump lube... so, some additives specific to carburettor ethanol-fueled spark-ignited engines were used, and eventually castor oil is used... instead of the ethanol offered in u.s., brazilian ethanol isn't blended with gasoline, and contains circa 4% water (e96h)...
 

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How do they get it to ignite under compression?
Scania's running 28:1 static compression in their diesel-ethanol engines. Does ethanol ignite at 18:1?
 

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Discussion Starter #3
How do they get it to ignite under compression?
Scania's running 28:1 static compression in their diesel-ethanol engines. Does ethanol ignite at 18:1?
ethanol just needs an adequated stratification to ignite at 18:1... in some conversions, the engines are fitted with pre-heated fuel lines... about scania, they use anhydrous ethanol with an ignition improver, unnecessary in brazilian conversions...
 

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Surely it's easier to combust than diesel. I would think it knocks. Do you have to retard the timing? Is eth harder to ignite than diesel under compression?
 

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How's the power when running eth in diesel engines? Are there more precombustion events?
the ethanol is not so heavy as diesel, so you need a bigger volume, around 25%... if you consider that a flexfuel vehicle needs 30% more ethanol than gas to run the same distance, you see that it's still a good deal in brazil, specially for ethanol producers...
 

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Discussion Starter #7
Surely it's easier to combust than diesel. I would think it knocks. Do you have to retard the timing? Is eth harder to ignite than diesel under compression?

no problem with timing... you just need more fuel, and it don't knocks... but it requires more attention about the injection pump lubrication... adding 2-stroke oil, castor oil or even soy cooking oil can improve the pump's lubrication, as ethanol is not so "greasy" as diesel...
 

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what about cng. i want to do cng. is it good to do a mix withh diesel or better to go straigt cng?

you can mix the cng with diesel.
 

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Discussion Starter #11
what about cng. i want to do cng. is it good to do a mix withh diesel or better to go straigt cng?
you can mix diesel with cng... cng needs a spark to ignite, that can be provided by a small amount of diesel... this setup is used in a thai version of chevy colorado... but you can convert a diesel engine to dedicated cng, then the engine would opperate in the otto cycle... you must change cyl heads, use a regular spark ignition and replace the injection pump by a throttle-body injection or a carburettor...
 
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