Forum Discussion
steveh27
Oct 12, 2018Explorer
Ethanol will absorb some water, I think less than 1%, so it can remove some water from the tank vs regular gas. But, once it surpasses that small % it will then permanently phase separate. The alcohol will come out of the gas & merge with water as a separate layer on the bottom of the tank. It will never go away and must be drained. The top layer of remaining gas will lose around 3 octane, ie 87 octane will become 84 octane.
https://www.boatus.com/magazine/2011/december/ethanol.asp
https://www.boatus.com/magazine/2011/december/ethanol.asp
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