Add Yahoo as a preferred source to see more of our stories on Google. A man changing the spark plug on a lawn mower - Fertnig/Getty Images If you own a gas-powered lawn mower, whether it is a compact ...

If your lawn mower runs on gas, then you've got a spark plug tucked inside the engine that plays a bigger role than you might think. Spark plugs are what fire up the engine in the first place. They ...