Bad gasoline is the most common cause of small engine failure. Identifying and avoiding bad gasoline well help keep gas-powered equipment running smoothly.

Step 1: Smell the gas. Gas contains volatile compounds that allow it to burn. As these compounds evaporate, gas becomes less combustible and eventually turns into a gummy varnish-like substance. When this happens, gasoline no longer smells like gasoline; it smells like pungent varnish.

Step 2: Look for discoloration or particles in the gas. Good gas is virtually clear. As gas turns bad it darkens, eventually turning a deep amber color. Empty cans and tanks often contain old gas deposits. When new gas is added, these deposits break loose, clogging the fuel line, fuel filter and carburetor. Rust from metal gas cans, dirt and yard debris can also make their way into gas and wreak havoc on small engines.

Step 3: Watch for separation. Water and gas do not mix. The ethanol in gas attracts moisture, and weather changes cause condensation in gas cans and gas tanks. Water is heavier than gas and will form a separate layer below the lighter-weight gas. Smaller amounts of water will appear as bubble-like spheres rolling around beneath the top layer of gas. Water causes the engine to run poorly and damages the fuel tank, along with many other engine parts.

Step 4: Properly dispose of bad gas by taking it in a sealed container to the local hazardous waste facility. Get rid of old gas cans at the same time.

Step 5: Reduce the possibility of bad gas by using new gas cans and keep them full throughout the year. Store gas containers away from direct sunlight, preferably in a temperature-controlled facility.

Step 6: Always add gas stabilizer to gas before storing it for any length of time. Protect small engines by adding gas stabilizer to the tank when running the equipment a final time. Top the tank off with fresh gas and tightly cap the tank before stowing the equipment away.

Step 7: Before using any gas that is more than two months old, shake the can and pour some of the gas into a glass container to examine it. Shine a light into the tank or can to check for water or debris. Take a quick whiff of it. If it doesn’t look and smell like gas, it is not gas anymore.

— Have a home improvement question for Fix-It Chick? Email it to Linda Cottin at hardware@sunflower.com.