When your vehicle has been in storage for a long time with fuel in the engine, the fuel will start to evaporate. However, a fuel stabilizer, when added to the fuel, acts as a protective layer.
A fuel stabilizer is made of petroleum products that bond with gasoline and prevent its evaporation. This also prevents the fuel from damaging the carburetor. It does this by acting as an antioxidant that stops the chemical breakdown of the fuel. It also absorbs water so that the fuel does not do it and remains at full strength.
Here we will discuss the best fuel stabilizers on the market. There are different types of fuel stabilizers with different chemical compositions. You have to check the compatibility of the stabilizer with the type of fuel you are using as well.
- Best Fuel Stabilizers Comparison Table
- Top 5 Best Fuel Stabilizers In 2021 Reviews
- Best Fuel Stabilizers Buying Guide
- Benefits of Using Fuel Stabilizer
- Types of Fuel Stabilizer
- Top Brands
Best Fuel Stabilizers Comparison Table
All Gasoline Engines.
32 Fluid Ounce
|(5 / 5)|
|(4.6 / 5)|
32 Fluid Ounce
|(4.8 / 5)|
Star Tron Additive (14308)
8 Fluid Ounce
|(4.9 / 5)|
Star Tron Enzyme Fuel Treatment
All Diesel Engines
32 Fluid Ounce
|(4.7 / 5)|
Top 5 Best Fuel Stabilizers In 2021 Reviews
1 STA-BIL (22214) Storage Fuel Stabilizer
STA-BIL model number 22214 is a storage fuel stabilizer. Storage stabilizers keep fuel fresh while under storage for a quick and easy start. It also absorbs water to prevent corrosion. This keeps the carburetor and fuel injectors clean and in good condition.
Since this product prevents gum, varnish, rust, and corrosion, it prolongs the life of the engine. When you start your vehicle after a while, you need to drain the fuel, which can take about 20 to 30 minutes. Using this storage fuel stabilizer means you don’t need to drain the fuel and the engine starts quickly.
This product can also be used in generators, bulk gas storage, as well as collector cars, small engines, and boats. It is effective in both ethanol and gasoline-based fuels and engines.
You have to use one fluid ounce of this stabilizer for every two and a half gallons of gas. You can also add the stabilizer to the gas can so that any equipment you fill with this can will have the fuel stabilizer.
Always make sure that the fuel stabilizer is added when the gas is fresh, probably at the gas station when you fill your tank. It will keep the fuel fresh and at full strength for up to 24 months.
STA-BIL has been making stabilizers for over 50 years, and they make storage, diesel, and marine stabilizers. Their products are some of the best in this category.
- It is compatible with all gasoline and ethanol blends.
- Keeps fuel fresh for two years.
- It is usable in collector cars, boats, generators, and small engines.
- Comes at a very low price.
- It becomes unstable after two years.
2 Royal Purple Max (11722) Clean Fuel System Cleaner and Stabilizer
Purple Max’s Max Clean is a fuel system cleaner and stabilizer that deeply penetrates and cleans injectors, carburetors, intake valves, and combustion chambers and restores fuel economy. It also reduces engine buildup and harmful emissions.
This product uses a proprietary technology that works on both the intake system and combustion chamber and is compatible with all types of engines, old and new, gasoline and diesel, naturally aspirated, turbocharged, and supercharged.
Royal Purple conducts tests of its products on engines of different makes and models. Those tests conclude that the use of Max Clean once improves the fuel economy on average of 3.2 percent and increases horsepower on average by 2.6 percent.
It also reduces hydrocarbon, NOx, and CO emissions by 12, 13, and 18 percent, respectively. It also prevents rough idling and stalling by stopping premature spark plug fouling.
As a result of fuel combustion, there are deposit build-ups in the engine, causing a significant effect on the performance and reliability of the engine. Max Clean keeps the engine clean, prevents engine knocking problems, and restores lost fuel economy.
This product is compliant with the standards of the Environmental Protection Agency and California Air Resources Board for use with gasoline and diesel engines.
It is compatible with all ethanol blends, biofuel, 4-cycle engines, and 2-cycle engines, and is safe to use with specialized emissions equipment. Its recommended usage rates are one can of 20 fluid ounces every 10,000 miles.
- Improves fuel economy by 3.2 percent.
- It reduces harmful gas emissions from the engine.
- It is usable in both diesel and gasoline engines.
- EPA and CARB compliant.
- The liquid and vapors are combustible.
3 Yamaha ACC-FSTAB-PL-32 Fuel Stabilizer and Conditioner
This Yamaha fuel stabilizer is recommended for E10 fuels. Its formula helps prevent fuel oxidation and phase separation.
E10 fuels are 10 percent ethanol, which can have some corrosive effects on metal. This product has an ethanol-free composition specially designed for such fuels to prevent varnish, gums, and corrosion caused by oxidation.
It is one of the best products for protection against ethanol fuel corrosion, but it can also be used with non-ethanol fuels.
Yamaha fuel stabilizer and conditioner will keep the fuel fresh and at full efficiency for about one year. It also prevents gum and varnish from building up in the carburetor by dissolving them.
It also has metal filmers or corrosion inhibitors to provide protection against corrosion for steel and aluminum components in the carburetor and fuel systems. Sometimes, when gas tanks fill with air, the moisture builds up ice clogs.
Using this product prevents this icing and gas line freeze from happening as it absorbs the moisture. Absorbing water also keeps the spark plug safe.
The normal dose for this is one fluid ounce of fuel stabilizer and conditioner to every three gallons of fresh gasoline. If you plan on keeping the engine idle for over two months, you need to add one fluid ounce of fuel stabilizer and conditioner to every one gallon of fresh gasoline.
This will be the best option for Yamaha engines and vehicles, as it is an original Yamaha product.
- It has metal filmers that protect steel and aluminum parts.
- Prevents corrosion in the fuel systems.
- Stops varnish and gum deposits.
- Prevents icing and gas line freeze in the carburetor.
- Only usable for about one year.
4 Star Tron Additive (14308)
Star Tron uses a proprietary blend of enzymes tested by the company StarBrite. They improve the combustibility of all types of fuels, including ethanol-blended fuels. This means your fuel will be at its best efficiency and will not be wasted due to evaporation and water.
This product cleans the fuel delivery system, which includes the tank, carburetors, and injectors. Having a clean engine and oil means your engine will start easily and run strong.
It is made for and prevents ethanol fuel problems. It also helps prevent phase separation. Phase separation occurs when a lot of water gets in the fuel and creates a separate layer, hindering combustion. This product stops the phase separation by scattering sub-micron-sized water droplets in the fuel that can then be easily removed.
This blend of Star Tron will keep your fuel fresh and stabilized for up to two years. It will remove any gum, carbon, and varnish in the engine.
The treatment quantities are one fluid ounce for six gallons of fuel. It is compatible with all engine types and fuel. It is suitable for use in boats, cars, trucks, motorcycles, small equipment, and engines that use pre-mix fuel. Basically, all gas engines will work.
- Cures any ethanol fuel problems.
- It removes gum, carbon, and varnish from the fuel.
- Usable with all gas engines.
- It helps prevent phase separation.
- Harmful when it comes in contact with the skin.
5 Star Tron Enzyme Fuel Treatment
Since this fuel treatment enzyme stops the oxidation and evaporation of fuel, it improves the fuel economy. All fuel is properly and uniformly consumed. It will help the engine start easily and run smoothly. It also reduces fuel emissions by removing gum, varnish, and carbon build-up from burners, injectors, and exhaust components hence keeping these components and the environment clean.
This stabilizer will stabilize and protect the fuel for up to two years. It can also be added to old fuel to help rejuvenate it. It will prevent phase separation by breaking down and distributing small water droplets throughout fuel that can easily be burned away when the engine is running.
Star Tron can be used in large applications and in all engine and fuel types, including heating oil, which is used in furnaces and boilers. Using this product will help the engine start easily and run smoothly, even after months of no use.
When adding for the first time, you should add one fluid ounce for every 16 gallons of fuel. When refilling, add one fluid ounce for every 32 gallons of fuel. It is compatible with all engines and is not harmful if overdosing occurs.
- It significantly reduces soot.
- Usable for all diesel engines.
- Safe to use with all fuels, including heating oil.
- Improves fuel economy and efficiency.
- It is fatally dangerous if swallowed.
Best Fuel Stabilizers Buying Guide
As there are different types of fuel and engines, the fuel stabilizers that go with each of those also differ. Depending on the composition of the fuel (ethanol, non-ethanol, or heating oil), the formula of the stabilizer will differ as well.
Ease of Use
One of the major benefits of this product is that you save time by making sure your engine starts quickly and eliminates the need for fuel draining. Similarly, adding fuel stabilizer to the engine should be a quick and easy process. It should not have complicated mixing ratios; instead, it should require you to only pour it in the tank.
Before adding the stabilizer to your fuel, you need to check if it will work with your fuel type and engine type. Gasoline, diesel, and ethanol fuels all have different requirements. Therefore, manufacturers specially formulate stabilizers for each type of fuel.
The stabilizer can, or bottle, will have the compatible fuel type written on it along with the correct amount that should be used per gallon. This also translates to engine type compatibility. Diesel engines will need different stabilizers than gasoline engines.
Sometimes, the amount of ethanol also affects performance. For instance, the Yamaha stabilizer we reviewed above was made specifically for E10 fuel (10% ethanol).
Price and Brand
The average price of fuel stabilizers is around $10-$35. It can vary according to the size of the can and the company. Quality should come first, so buying from a trusted and high-quality brand is the wise thing to do.
You should also keep in mind how much of the stabilizer you have to put in per gallon. A cheap bottle is not worth much if it does not last long. Choose the product that has a balance between budget and stabilizer per gallon of fuel.
After some time, the fuel stabilizer will stop having its effect, and you will have to add more. The standard time is two years. Most of the stabilizers will keep the fuel clean and efficient for two years. Some fuel stabilizers last for a year only.
All fuel stabilizers remove any varnish and gum from the engine and absorb water to prevent phase separation. Some products are also great at removing carbon build-up inside the engine. This reduces soot and harmful emissions.
You should also look for stabilizers that prevent corrosion and protect metal components.
Benefits of Using Fuel Stabilizer
To make your engine work at its optimum level, a lot of different components work together. You have to use the best fuel, filters, and stabilizers along and properly maintain all engine parts.
If you skip any of these things, you will notice a decrease in performance. It is, therefore, important to know all the things that make these products worthwhile.
The combustion process of the fuel has by-products like soot and carbon deposits in the engine. If fuel is stored for long periods of time, it will start to evaporate. The efficiency of the fuel is also compromised when it comes in contact with moisture.
All of these issues are removed by adding a stabilizer. A stabilizer prevents phase separation by dispersing sub-micron water particles that are easy to remove. It prevents oxidation; hence the fuel remains at full capacity.
Over time, the engine components start to get corrosive, which affects the performance. High-quality fuel stabilizers have metal filmers that prevent corrosion. Since these products also remove gum and varnish, they protect the engine as well as the fuel from harm.
A lot of things affect the efficiency of the fuel. Moisture, when added to fuel, reduces its capacity. Evaporation reduces fuel economy. You run out of fuel very fast and end up paying more. Using stabilizers keeps the fuel at full efficiency and saves you money.
No Dry Starts
A brand new engine or an engine that has been sitting idle for a long time takes some time to start at first. This happens because of a dry start, that is the time between the engine starting and the oil lubricating all the parts. This time increases when the engine has not been in use for a long time.
Adding a fuel stabilizer means you don’t have to drain fuel when storing the engine. This leads to a quick and easy start to the car.
Types of Fuel Stabilizer
Depending on how you are going to use it, there are basically two types of fuel stabilizers.
Using fuel stabilizers for storing your vehicle or any other engine is the main benefit of fuel stabilizers. Stabilizers meant for storage are designed to provide a longer treatment time.
Once you add the stabilizer, it should keep the fuel fresh, stable, and at full capacity for at least a year. Most good-quality products will give two years of protection time.
This type of fuel stabilizer is better at removing and dissolving impurities in the fuel like carbon, gum, and varnish. It keeps the fuel at its optimum efficiency level by ensuring proper combustion. Performance-based fuels do, however, have lower protection time.
There are many companies that make car or engine-related products. Out of all those, these are the ones that will give you the best quality and the most reliable products when it comes to fuel stabilizers.
This company has been in the fuel additives business for over 50 years and is a subsidiary of Gold Eagle Co. They cater to all kinds of engines and fuel types, including engines of cars, snowmobiles, and boats. Specialized blends are made for all these different types because every engine is not the same.
Their products have recommendations from over 100 original equipment manufacturers. They have four product categories, i.e., storage fuel stabilizer, marine fogging oil, diesel fuel stabilizer, and marine fuel stabilizer.
Storage stabilizer is for when you plan on storing your engine for several months without use. Diesel stabilizer is for diesel fuel and engines that operate on diesel like tractors and generators.
Marine stabilizers specialize in preventing corrosion from lead found in the fuel and removing water. They can be used with ethanol-blended fuels as well and are recommended in high moisture environments.
Sea Foam was founded by Fred Fendri in the 1930s as a result of working on fuel problems of outboard motors. Their goal is to make products that make engines and equipment cleaner and more durable.
Their original formula was based on petroleum, and it was used to keep the fuel fresh and the motor clean. Sea Foam’s products don’t use any harsh chemicals; instead, they only have safe petroleum-based lubricants.
StarBrite was founded in 1973 by Peter Darnau. Their initial focus was on boat maintenance, but they also make products for cars, RVs, and ATVs, etc. Their best product is the Star Tron Enzyme Fuel Treatment. It is a top-rated product.
They also make vehicle appearance and maintenance products. They have expanded their reach to aircraft, home care, aviation, lawnmowers, motorsports, and motorcycles.
Royal Purple was founded in 1986 by John Williams. They are one of the largest American manufacturers of lubricants for marine, automobile, and industrial use. They also serve in other countries, including Australia, Canada, China, Italy, Japan, Mexico, and the United Kingdom.
Their products include motor oils, racing products, lubricants, performance additives, grease, and engine oils.
You add things to your fuel or engine to improve your performance and efficiency. However, adding harmful products will not only reduce engine performance but also make it less durable. Even after you have chosen a safe and high-quality stabilizer, you need to make sure you use it correctly for it to work.
Here are some tips to keep in mind.
- Check the bottle label for instructions on the amount of stabilizer to add per gallon.
- It is advised to add the stabilizer when the fuel tank is nearly empty. You should do it when you are adding fuel at the gas station.
- Add the fuel after the stabilizer.
- To make sure you get the best from the product, you need to run the engine for about five to ten minutes.
- Running the engine like this makes sure that the stabilizer reaches the entire engine before you start driving.
- Adding extra stabilizer can sometimes be damaging to the fuel, so make sure you read the warnings. Some products are safe when overdosed.
To sum up, the STA-BIL Fuel Stabilizer is our top pick for the best fuel stabilizer. It has a very reasonable price and can be bought in various quantities, including a one-gallon bottle.
It is compatible with both ethanol and gasoline-based engines and will provide protection for two years. Two years is the best treatment time for storage-based fluid stabilizers. It is also our first pick because it is compatible with all engine types.