Ethanol Shield

What It Is

Ethanol Shield is a fuel stabilizer and treatment designed to counteract the damaging effects of ethanol-blended gasoline in small engines. It’s for lawn mowers, trimmers, chainsaws, leaf blowers, and any outdoor power equipment that uses E10 or E15 fuel.

Fitment & Compatibility

• No physical fitment – Ethanol Shield is a liquid additive, not a replacement part. It works with any gasoline engine that uses ethanol-blended fuel.
• Check your fuel type – Use only if your machine runs on E10 or E15 (common at most pumps). Not needed for pure gas or diesel engines.
• Fuel tank size – The standard 8 oz bottle treats up to 8 gallons of fuel. For larger tanks (e.g., zero-turn mowers with 3+ gallon tanks), you may need multiple bottles per season.
• Brand/model agnostic – Works with all brands (Honda, Briggs & Stratton, Kawasaki, Toro, etc.) and both OEM and aftermarket fuel systems.

Key Things to Know

• Quality – Highly rated (4.7/5) for preventing phase separation and corrosion. Users report fewer carburetor issues and easier starts after storage.
• Installation difficulty – Dead simple: pour the correct amount into the fuel tank before filling with gas, then run the engine for 5 minutes to circulate the treated fuel.
• Common gotchas – Don’t over-treat; follow the dosage on the bottle (1 oz per gallon). Treating old, already-deteriorated fuel won’t fix it—add to fresh gas. This is a preventive measure, not a cleaner.
• Storage tip – Best used before winter or long idle periods (more than 30 days). Treat the last tank of the season and run the engine dry.

Should You Buy It

Buy Ethanol Shield if you store your mower for more than a month, deal with ethanol fuel in your area, or want to avoid carburetor gumming and starting issues. It’s a cheap, easy insurance policy for any small engine that sits idle. Skip it if you only use ethanol-free gas or run through a full tank every week.