When i heated up the olive oil until the foam came, leaved the oil in constant heat (Kitchen oven are electric) and simmed away until the foam dissapeared. Then i heated up a bit more, the foam came again, but less than before, simmed still away until the foam dissapeared and heated up more again, the foam was not there longer and the smoke came from oil. Also the oil got increased boiling point than natural olive oil. It is important the oil must not burn in the diesel engine in case lube will be disappeared in cylinder. I ran the engine, there was enough oil out of exhaustport as a sign the oil was not burned away in the engine. See my engine: http://www.youtube.com/watch?v=wmH6WUMUEJg

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