Best Fuel Stabilizer for Small Boat Engines
  • Post author:
  • Post last modified:October 7, 2020

Disclaimer: As an affiliate I may earn a commission on any qualifying purchases, including those from, at no extra cost to you – read more.

Our Review of Fuel Stabilizers for Boat Engines

The Ethanol in your boat’s fuel tank is an extremely powerful solvent. In fact, it’s so powerful that it can render some fiberglass fuel tanks completely useless. Ethanol can also absorb moisture from the air, which as a result, can damage some components of your boat significantly.

If you plan on storing your boat and you want to keep the engine safe from the negative effects of Ethanol, you’ll need a high-quality fuel stabilizer. Lucky for you, we’re about to reveal our top picks for the best fuel stabilizer on the market today, so stick around.

STA-BIL 360° Vapor Technology Marine Fuel StabilizerBest Fuel Stabilizer for Small Boat Engines

If you’re planning on storing your boat for about a month or two, we highly recommend this fuel stabilizer from Amazon because it’s designed mainly for storage, not regular usage. Not to mention that this is one of the most affordable fuel stabilizers available, so you don’t have to worry about shelling out a whole lot of money. The STA-BIL 360° is also perfect for holiday-home boat storage.

For a fuel stabilizer of its price range, the STA-BIL 360° sure has a lot to offer. It’ll help prevent the fuel from separating and going bad, allowing you to use it whenever you decide to unleash your boat from its dormant state. In addition, it will help protect your engine from any rusting that fuel can cause in storage. It can keep gasoline fuel fresh for up to 24 months of storage.

There are a few things you need to do, however, if you plan on buying this fuel stabilizer. Firstly, it’s highly recommended to inject the stabilizer to an empty tank before filling it with fuel so that it mixes properly. And secondly, after adding the stabilizer, you want to turn on your engine for a few minutes in order to ensure that the stabilizer is recognized in the boat’s fuel system.

Another thing we highly recommend doing is that you top out the fuel tank so that you eliminate the chances of extra condensation, which is pretty common in boats that are in storage. Overall, the STA-BIL 360° is an excellent fuel stabilizer that will keep your boat well-protected and your fuel fresh for a very long time.


  • Highly affordable price tag
  • Offers great rust protection
  • Features vapor technology
  • Great for gasoline engines


  • Not for Ethanol engines
  • Not for regular usage

Star Brite Star Tron Enzyme Treatment Fuel StabilizerFuel Stabilizer Outboard Engine

The Star Tron Enzyme Treatment (Check Amazon) fuel stabilizer from Star Brite is an ideal product for Ethanol engines. Its way of treating Ethanol is like no other stabilizer. Basically, it breaks down the gunk and water present in fuel in order to keep it fresh and clean, which allows for better combustion and greater efficiency. This also helps reduce the fuel’s emissions and enhance its performance.

The great thing about this product is that no matter how old your boat is, it’ll manage to keep it running smoothly and safely. It’ll put an end to stoppages from your fuel lines and provide great protection against rust for your engine. With Star Tron Enzyme Fuel Treatment, you don’t have to worry about the negative effects that are associated with using standard Ethanol fuel.

Not only does Star the Tron Enzyme Fuel Treatment fuel stabilizer work on Ethanol engines, but it’s also perfect for gasoline engines. Moreover, you can use it for both regular use and storage. It’s capable of keeping the fuel fresh for up to two years of storage. If you’re in the market for a fuel stabilizer that’s great for both in-season and out-of-season treatment, this is your best bet.


  • Great for Ethanol and gasoline
  • Ideal for regular use and storage
  • Stabilizes fuel for up to two years
  • Capable of rejuvenating old fuel


  • Not specifically for marine use
  • Not the best for large engines

STA-BIL 22275 Ethanol Treatment Fuel Stabilizer

STA-BIL Ethanol Treatment (Check Amazon) is regarded by many as the absolute best fuel stabilizer for storage and in-season use, but is it? Well, we can definitely see why it’s at the top of everyone’s list and we couldn’t agree more. This stabilizer will help you remove water and prevent condensation in Ethanol fuels, keeping your boat’s engine safe. It’s also pretty affordable compared to others.

This fuel stabilizer boasts Vapor Technology which basically eliminates condensation completely from the fuel when stored for a long period of time. As a result, the fuel remains fresh and the engine remains well-protected against corrosion. While this fuel stabilizer is ideal for storage, we wouldn’t say it’s designed for long-term storage. It’s geared more towards in-season usage.

If you’re someone who uses their boat for half a year and stores it during the other half, this is a perfect, all-round fuel stabilizer. During the off-season, it will keep your engine well-protected, and in-season, it will keep your fuel clean and have it functioning at maximum efficiency. All in all, a highly recommended product for boat-owners that have Ethanol engines.


  • An ideal pick for Ethanol engines
  • For storage and in-season usage
  • Great protection against corrosion
  • Prevents condensation completely


  • Not suitable for long-term storage
  • Not for use on gasoline engines

LUCAS LUC10013 Fuel Treatment Fuel Stabilizer

While most fuel stabilizers on the market aren’t designed specifically for marine use, Lucas Fuel Treatment (Check Amazon) is one of the few ones that are geared primarily towards the marine environment. It’s perfect for boats that run on engines that use Ethanol fuels such as E10 and E15, which we all know tend to absorb moisture from the air like crazy.

Lucas Fuel Treatment is ideal for regular use and it will keep the fuel in your boat’s tank free of water, but it’s not really designed for storage. However, this is a remarkable fuel stabilizer when it comes to ridding you of the negative effects of Ethanol such as damaging gaskets, fuel lines, and other rubber or plastic parts of boat engines. It’ll keep your engine safe from corrosion.

The thing we love the most about this fuel stabilizer is that comes in a large quantity while still being super affordable, which is highly convenient considering that it’s designed for regular use. This is also perfect if you’re trying to stabilize more than one engine. Using this stabilizer, you’ll be saving a lot of money that you would have otherwise squandered on gas and maintenance.

The fact that this fuel stabilizer removes all the impurities present in the fuel grants you much better performance and more mileage than you’d expect to get from a tank, allowing for smooth operation. However, we feel the need to stress that this fuel stabilizer isn’t designed for storage, so you should only use it in season.


  • Great for Ethanol engines
  • Gets rid of all impurities
  • Keeps the fuel water-free
  • Grants you more milage


  • Not designed for storage
  • Not for gasoline engines

Things to Consider Before Buying a Fuel Stabilizer

In order to ensure the best bang for your buck and rest assured that your engine is safe and that your fuel is kept clean, there are a number of factors that you should take into consideration when in the market for a fuel stabilizer. These factors are:

Engine Compatibility

Before buying a fuel stabilizer for your boat, you need to carefully inspect whether it’s designed for the type of fuel that your engine runs on. For instance, if your boat runs on Ethanol, you can’t go for a fuel stabilizer that’s designed for gasoline. We advise going for a stabilizer that works with most boat engines so that you can be on the safer side.

Storage or Regular Use

Not all fuel stabilizers are designed for long-term storage. Fuel stabilizers that are designed for storage tend to feature vapor technology which helps absorb moisture, keeping your fuel free of water and well-protected from rust. This is especially important for engines that run on Ethanol since Ethanol attracts water over time.

If storage isn’t really your aim and you’re simply looking for a stabilizer that you can use to top your tank on season, then you’re likely to find plenty of high-quality products. Using a stabilizer regularly will help prevent misfires and it will keep your engine healthy in general. Before buying a fuel stabilizer, make sure that it indicates whether it’s designed for regular use or storage.

Ease of Use

The fuel stabilizer that you’re going to buy should be easy to use. Not only that, but you need to ensure that it can be stored with ease as well. Typically, you shouldn’t start your boat’s engine before ensuring that the fuel stabilizer is mixed properly with the fuel.


There are plenty of other high-quality fuel stabilizers that are great for marine environments, but the above-mentioned products are simply the top of the line. If we have to select a winner, we’d go with Star Brite Star Tron Enzyme Treatment Fuel Stabilizer just for the simple fact that it works for both Ethanol and gasoline engines, and because it’s perfect for both regular use and storage.

John Allen

With more than a decade of experience cruising the lakes in my Crestliner Grand Cayman pontoon boat and my Boston Whaler, I now want to share everything I've learned with my community here at Boating Hub.

Leave a Reply