I’ve been fairly lucky to avoid much in the way of problems due to ethanol in fuel. Probably as I’m fairly careful about not leaving old stuff in tanks. However, this year I ended up with 3 lawnmowers none of which would start. It turned out it was not clogged jets but rather the petrol in the tanks had absorbed enough moisture to separate out the ethanol as a separate layer (see lower pic). Unfortunately, you only need a small amount of water in the fuel to trigger a complete phase separation of the ethanol from petrol. The lower (ethanol/water phase) sinks straight to the bottom of the tank so ends up in the carb. I suspect it was a bad batch of petrol that had some water in but even so I’m going to be more careful from now. However, it seems a shame to waste the petrol. Fortunately, you can use this undesirable property of ethanol to get rid of it from the fuel.
You can get buy kits for stripping the ethanol out of petrol but I’m a stingy sod so I made up a separating funnel out of some stuff I had lying around for the grand sum of £0 (see upper pic). The vent at the top is a little crude (a simple bung) but works fine with care and I can process half a gallon or so at a time. All you need is to add enough (eg 100ml) of water and shake which will separate the ethanol out of the fuel. Allow to settle then draw off the undesirable water/ethanol layer from the bottom. I guess the octane is a bit down afterwards but it should be fine for lawnmowers and low compression Scotts 😀 Perhaps, adding an octane booster may be advised?
Keith
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