Ethanol, created by blending gasoline and ethyl alcohol, is added to gasoline to make an environmentally friendly product and to help conserve fuel resources. Ethyl alcohol is grain alcohol that has been used in vehicles since the 1970s. In recent years, ethanol has been shown to cause problems in small engines, such as those found in ATVs, recreational watercrafts, boats and lawnmowers, and consumer warnings have been issued by some manufacturers.
Consumer Affairs reports that ethanol fuel is particularly harmful to some vehicles, especially boats, because of a process known as phase separation. Phase separation occurs because ethanol attracts and binds with water. When ethanol absorbs too much water, the ethanol and water separate from the gasoline, leaving behind a layer of water that can seriously damage an engine when the vehicle attempts to burn fuel. Lawnmower manufacturer Briggs and Stratton does not recommend leaving ethanol fuel in engines for more than 30 days without adding fuel stabilizer to the engine.
The alcohol content in ethanol could cause engine corrosion. Ethanol gasoline has been known to break down engine seals, dissolve fiberglass gas tanks in boats and destroy plastics. Over time, ethanol's corrosive properties can lead to engine failure, especially if corrosion winds up in the engine causing clogs and fuel blockage.
Though small engines get better fuel mileage than their larger counterparts, ethanol fuel burns faster and decreases overall fuel efficiency. This means that the gasoline you put in a small engine can be consumed more quickly when it contains ethanol.
