You’ve probably walked past the bottle on the store shelf, or you’ve heard someone say they had to stabilize their fuel for storage. Today’s ethanol-blend gasoline degrades over time, whether the bottle sees daylight or it’s stored in a cool dark place. You have to protect your vehicles, lawnmower, motorcycles, and watercraft from fuel going bad and clogging the fuel system. If you’ve never tried a fuel stabilizer, or never understood why you should be using it, we’ll break down what it is and why you need to use it.

How Fast Does Gasoline Go Bad?

Time affects everything, and gasoline is no different. Gasoline starts to break down in as little as 30 days. That breakdown causes the varnish you find in carburetors, and deposits that clog fuel filters and injectors. Old gasoline oxidizes so much that it won’t readily ignite. That may be hard to imagine, but it can change big time if left to the hands of time.

Gasoline is made up of carbon and hydrogen atoms that combine to form hydrocarbons. It’s made from a process turning crude oil into an energy-dense fuel. Heat, pressure, and additional factors form the gasoline molecules.  Refineries add a mixture of ethanol between 10% (E-10) and 85% (E-85) to create the fuel.  However, they do not add stabilizer to protect the fuel from oxidation and breakdown.

Why Ethanol Hurts Gasoline

Your local gas station may not have ethanol-free gasoline, but if it does you will find a group of fuel consumers that will swear by ethanol-free gas.  Ethanol attracts water and will absorb moisture into the gasoline. That moisture won’t cause a lot of damage in a very small quantity but left to absorb a great deal over time it can cause fueling issues in any fuel system. A large amount of moisture mixed with gasoline will cause phase separation. Gasoline and ethanol will separate, much like oil and water, and that separated ethanol can cause a no-start condition in any engine.