Stale Gas Could Be Killing Your Small Engine

Small-engine mechanics tell us that stale gas is what keeps them employed and busy.

Stale gas causes the vast majority of starting problems, which usually lead to a carburetor rebuild or replacement ($100). But if you follow a few simple rules, you can avoid hard-starting hassles and repair costs. Here’s how.

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Buy smaller quantities

Add stabilizer every time you fill

Get a new gas container

Filling and storage tips

Let the engine cool after use and then refill the tank to 90 percent. That will reduce moisture condensation and oxidation.

Consult your owner’s manual for off-season storage recommendations. Most manuals specify “dry storage,” which involves draining the tank and running the engine until it dies. Then pull the cord until you get no signs of life from the engine. If the manual recommends “wet” storage, fill the tank to 90 percent with fresh stabilized gas.

Use the right kind of gas

Never use E-85 or E-15 gas in your small engine. Those fuels can cause catastrophic damage.

Most small engines operate best with 87-octane fuel (85-octane in high altitudes). Unless specifically recommended by the manufacturer, never use a higher octane fuel in your small engine.

Choose long-life gas for occasional use

Is ethanol why your engine won’t start?

Everybody blames oxygenated fuel (gas with ethanol) for carburetor failures. But guess what caused the problems before we started adding ethanol? Yup—stale gas. We’re not saying that gas with ethanol is the perfect fuel. It’s not. But the truth is, whether you buy oxygenated or non-oxygenated gas, operator error is really the root cause of carburetor corrosion and gunk buildup. Gasoline simply goes bad, and it goes bad faster if it’s improperly handled and stored. You can avoid all gasoline-related starting problems by following these simple buying, storing and usage tips.

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