Best Fuel Stabilizer For Small Engines

By stabilizing existing fuels while in storage, fuel stabilizers from trusted companies can help keep small engines safe and reliable. Fuel oxidation can occur in your vehicle’s engine if it has been running for a long period of time. This can lead to engine damage. Here is a list of the top ten best small engine fuel stabilizers available on the market to help you prevent these mishaps.

Although most of the fuel stabilizers on this list are only suitable for small engines, cars, and boats, most of them are also compatible with 2-stroke and 4-stroke engines.

Sta-Bil vs Seafoam


Sta-Bil is a glycol-based substance that works similarly to antifreeze in a petroleum-based liquid, such as gasoline, to keep things from freezing. Once it has been added to gasoline, it creates a thin layer on top of the fuel, which is very effective at keeping out air and moisture. For any reason or in any way, if the gasoline container is moved or disturbed, the thin film immediately cracks and does not reseal.


While Seafoam is a brand known for its versatility (fuel stabilizer and cleaner), Sea Foam is a petroleum-based product that offers comparable protection, as well as providing the added benefit of cleaning the interior components as it burns. This means that regardless of whether you shake or tap the fuel tank, your equipment will not be exposed to moisture or air.

Best Fuel Stabilizer For Small Engines

1. Star Tron Enzyme Fuel Treatment

The enzymatic fuel treatment provided by Star Tron was the best option for us. By using this substance, which is put into the fuel stabilizer, ethanol fuel problems are prevented and eliminated by breaking down additional water and slime. Your vehicle would run smoother and more efficiently as a result of a cleaner fuel framework in place. Your average mileage is expected to increase significantly as a result of the improved performance.

STAR BRITE Star Tron Enzyme Fuel Treatment SEF Gasoline Formula - 1 oz. Treats 6 Gallons - 8 OZ (14308)
  • Makes engines start easily and run smoothly; improves MPG and reduces emissions
  • Stabilizes fuel for up to 2 years and can help rejuvenate old, sub-spec fuel
  • Cures and prevents ethanol fuel problems; helps prevent phase separation

2. STA-BIL 22214 Fuel Stabilizer

Using Sta-Bil to protect your engine against natural build-up or to keep it in good running condition while idling for long periods of time is a great option for many situations. It can keep your vehicle’s gasoline fresh for up to 24 months, allowing you to avoid having to empty the tank. After filling, the gasoline additive ensures that the vehicle starts quickly and easily.

Sta-Bil Fuel stabilizer is one of the most effective gasoline additives for long-term storage, although it is not suitable in all situations. If you are looking for an additive to improve the fuel economy of your daily vehicle, there are better alternatives. The formula developed by Sta-bil is suitable for gasoline-powered cars and equipment.

STA-BIL Storage Fuel Stabilizer - Keeps Fuel Fresh For Up To Two Years, Effective In All Gasoline Including All Ethanol Blended Fuels, Treats Up To 80 Gallons, 32oz (22214), Red
  • STORAGE – STA-BIL Storage Fuel Stabilizer eliminates the need to drain fuel and keeps gasoline fresh for up to 24 months. Never fear your car or small engine...
  • ENSURES QUICK, EASY STARTS – Treating your gas with this fuel stabilizer prevents gum, varnish, rust, and corrosion in your fuel tank, all of which are costly...
  • VERSATILE – STA-BIL Storage Fuel Stabilizer is safe for use in all gasoline engines, including 2-cycle. Use this fuel treatment in your vehicle, motorcycle,...

3. Sea Foam RV SF-16 Liquid

Sea Foam is a highly effective conservative fuel stabilizer that coats the engine when idling and cleans the fuel tank while the engine is running at high speeds. Cleaning the fuel system with Sea Foam removes carbon deposits and thoroughly cleans injectors, carburetor jets, and lines. When used properly, it can help prevent varnish deposits and internal impurities from building up on intake valves, pistons, and cylinders.

Sea Foam SF-16-2PK Motor Treatment Multi-Use, 16 Ounce, Pack of 2, 16. Fluid_Ounces
  • Dissolves and clean fuel deposits and sticky residues from gas and diesel fuel injectors, carburetors, and combustion chambers
  • Package dimensions :5.0" L x5.0" W x8.25" H
  • Does NOT have harsh detergent or abrasive chemicals that can harm your engine

4. STP Fuel System Cleaner and Stabilizer

When used in conjunction with STP’s fuel cleaner and stabilizer, it provides an economical and efficient way to prevent corrosion and fuel leaks in ethanol fuel systems. You can be prepared to use a single 12-ounce container to cover multiple engines for an entire season, as one 12-ounce container treats 40 gallons of gasoline. If you use it to clean a fuel system that is not severely gummed or rusted, you may not notice a big change in performance.

Ultra 5 In 1 Fuel System Cleaner and Stabilizer, System Fuel Cleaner Deep Cleans Fuel System and Fights Engine Friction, 12 Oz, STP
  • Formulated to help save gas and lower emissions by deep cleaning the entire fuel system
  • Formulated to help restore peak performance and reduce friction by lubricating engine parts
  • Formulated to help prevent ethanol deposits and inhibit corrosion

5. Lucas Oil Fuel Stabilizer

Lucas Oil Fuel Stabilizer is a reliable and risk-free solution to ensure the stability of gasoline in unused tanks. The formula is simple to remember: just one ounce for every gallon of water in the tank. Our favorite feature is the way Lucas Oil cleans the entire fuel system while the vehicle is stationary. This means that the performance of the carburetor, injector, and pumps will not be affected by rust.

Lucas Oil 10303 Fuel Stabilizer - 1 Quart
  • Application rate: 1 ounce to treat 1 gallon
  • Safe to use in all grades of gasoline and in all 2 and 4-cycle engines
  • Better solution to prevent gasoline break-down during storage

6. Schaeffer Neutral Fuel Stabilizer

Schaeffer’s Neutra gasoline stabilizer is a bit more expensive than the other options on our list, but it’s worth it for the convenience. Neutra is compatible with many types of vehicles, including petroleum, gasoline, and ethanol, so one gallon of Neutra may be all you need for several years. Because the container is often not tightly sealed, there have been occasional leaks, and both the 12-ounce and gallon sizes would benefit from a longer nozzle.

Schaeffer Manufacturing Co. 0131-004S Neutra Fuel Stabilizer, 1-Gallon Bottle
  • Optimizes performance and fuel economy up to 5%.
  • Lowers the freeze point of any water that may be present in the fuel.
  • Reduces emissions, exhaust smoke and particulates.

7. Mercury Quickstor Fuel Stabilizer

Mercury Quickstor fuel stabilizer is a reliable and safe solution for gasoline left in the tank. One ounce of kerosene is equivalent to five gallons of gasoline, making it a reliable method of winterizing the gas tank. This product is well known in the boating industry for the quality of boat engines, which are easily removable from the boat itself. It can also be used in cars, trucks, and other engines that run on gasoline or ethanol.

MERCURY Genuine Quickstor Fuel Stabilizer 12Oz - 8M0047932
  • One (1) 12oz. bottle - 1 ounce treats 5 gallons, 12 ounce bottle treats 60 gallons
  • Add to fuel before long-term storage of your engine, stabilize fuel for up to a year
  • Prevents regular and ethanol-blended fuel from breaking down and oxidizing

Things to Choose Best Fuel Stabilizer For Small Engines

1. Storage

Gasoline stabilizer is a storage-based solution that can keep fuel fresh for up to two years after its first use. Each has a formulation designed specifically for particular areas of protection, such as the storage of vehicles, generators, lawnmowers, and the like. Some claim to provide protection for up to three years, while most claim to do so for only two years.

2. Performance

Fuel-based stabilizers are available that can keep a vehicle clean for less than two years on average. Because of the impurities in gasoline, they act quickly and effectively to break down any buildup that has developed over time. Performance-based stabilizers are also available.

3. Compatibility

Each type of fuel stabilizer has a different formulation. Read the manufacturer’s information on the intended use of the additive and the amount needed per gallon. Using a gasoline additive that is incompatible with your fuel does not make sense.

How to Use a Fuel Stabilizer

Gasoline settles and deteriorates if it is not used within 30 days of purchase. In contrast, those who carry gasoline in a closed container are less likely to have the fuel damaged. The application of a gasoline stabilizer is described in more detail below.

  • The process is as simple as filling a gasoline tank with fuel. Ideally, the stabilizer should be applied with a full tank of gasoline, which is the recommended method. Check the gas tank to make sure there is the proper amount of stabilizer.
  • Use a combination of gas conditioner and gasoline to provide the greatest protection against discussion or exposure to water.
  • You have completed your task. Prepare to take the wheel of the car. Primary blending can be completed by running the utility’s engine for ten minutes at a time.


Can you use too much fuel stabilizer?

It is not recommended to add more than 1 ounce of stabilizer. If you do, you are likely to get detonation and loss of power.

How long does fuel stabilizer last?

Fuel-stabilized gasoline keeps for one to three years.

Does fuel stabilizer hurt your engine?

If a gasoline stabilizer is not applied, the result can be poor performance or an engine that does not start at all after many months of vehicle storage.

Final Thoughts

Investing in a high-quality gasoline stabilizer is a relatively affordable method of saving money on fuel while it is being stored, whether in the car’s tank, in a storage tank, or elsewhere. As stated above, it also helps to extend the life of the engine, due to the use of substances that clean and lubricate the engine. You have every incentive to start using it right now, and we are sure you will not be disappointed.


Cars were and will be my first love and favorite hobby; I decided to start writing about my discoveries and techniques to improve my cars or repair them.