Phase separation in gasoline containing Ethanol is now a major problem for all users of gasoline. Check your tank lids and make sure to siphon any water from around your drop tube to prevent corrosion and the need to chip out ice if it freezes. Phase separation describes what happens to gasoline containing Ethanol when water is present. When even small amount of Ethanol comes in contact with water, the Ethanol will pick-up and absorb some or all of that water. When it reaches a saturation point, the Ethanol and water will Phase Separate, actually coming out of solution and forming two or three distinct layers in the tank. This can cause clogged filters, stalled engines and corrosion. Ethanol has a high octane, over 100. If the Phase Separation happens, it lowers the gasoline’s octane to below 87, and makes it useless. So check those lids!