Stabilized Fuel: Color Change Chemistry Explained

Fuel stabilizers are a solution that provides a protective layer for fuel sitting in a gas tank. They are designed to prevent oxidation in fuel and typically made from petroleum products. Fuel stabilizers are particularly useful for people who own seasonal equipment, classic cars, or boats that tend to sit for more than three weeks at a time.

STA-BIL is a popular brand of fuel stabilizers with a range of products for different uses. However, one of the myths about STA-BIL is that all their products are the same, just with different colours. This is false, as each product is specially designed to address and prevent a unique set of problems. For example, STA-BIL Fuel Stabilizer keeps fuel fresh for up to 24 months, making it ideal for long-term engine storage, while STA-BIL 360° Marine provides defence for engines that perform in high-moisture, water-laden environments.

Another myth is that STA-BIL products change colour as they age. While the dye in STA-BIL does get darker as it ages, this is not an accurate way to determine whether the product is still usable. Instead, STA-BIL products have a shelf life of about two years, whether they have been opened or not.

How does stabilized fuel work?

Fuel stabilizers are a special type of liquid that can be added to fuel to prevent it from spoiling. They are particularly useful for seasonal equipment, classic cars, or boats that tend to sit for more than three weeks at a time.

Fuel is a dynamic liquid that can go bad if left to sit around. According to RoadandTrack.com, fuel starts to spoil after just 30 days, unless it’s stored in an entirely airtight container. As a car’s fuel system isn’t airtight, fuel stabilizers are often used to preserve fuel in out-of-use vehicles.

Fuel stabilizers are typically made from petroleum products and work by bonding with gasoline to prevent evaporation and the formation of sticky resins that can ruin a carburetor. They are also designed to repel water and limit evaporation.

To use a fuel stabilizer, you should first read the product instructions and ensure your vehicle has a nearly empty tank of gas. Then, you need to measure the correct amount of stabilizer and pour it into the gas tank before filling the tank with fuel. Finally, you need to run the engine for 5-10 minutes to allow the stabilizer to reach the entire fuel system.

Fuel stabilizers can preserve fuel for up to two years and can be used with all kinds of gasoline and diesel engines, including two-stroke motors. They are designed to maintain the quality of stored fuel and can prevent engine problems that might reduce fuel efficiency.

How long does stabilized fuel last?

Stabilized fuel can last for quite a long time, but it does depend on a few factors. Firstly, the type of fuel matters. Pure gas tends to degrade and lose its combustibility within three to six months, whereas ethanol-gasoline blends have a shorter shelf life of two to three months. However, stabilized fuel can last much longer. According to one source, STA-BIL, a popular brand of fuel stabilizer, can keep fuel fresh for up to 24 months. Another source claims that most fuel stabilizers will preserve fuel for a full year, and increasing the dosage may extend this period.

It's also important to consider how and where the fuel is stored. Heat, oxygen, and humidity all impact the condition of stored fuel. Gasoline should be kept in an airtight container, in a cool, low-oxygen environment. If exposed to high heat and humidity, the volatility of the fuel increases, along with the potential for fire and explosion. For this reason, it's not recommended to store more than five gallons of fuel.

Additionally, the quality of the fuel stabilizer itself matters. Some brands are formulated for use with gasoline or diesel fuel, while others are dual-purpose. It's essential to read the labels and instructions carefully to ensure proper usage.

Finally, while stabilized fuel can last longer, it's still best to use it within a certain timeframe. Generally, stabilized gasoline can be stored for up to 12 months, but for optimal performance, it's recommended to use it within 6 to 8 months.

What happens if you don't use stabilized fuel?

Fuel is a dynamic liquid that can go bad if left to sit around. According to RoadandTrack.com, fuel starts to spoil after just 30 days unless it's stored in an airtight container. As a car's fuel system isn't airtight, fuel stabilizers are needed to preserve fuel in out-of-use vehicles.

Fuel stabilizers are designed to prevent oxidation in fuel and extend its lifespan. They are typically made from petroleum products and bond with gasoline to prevent evaporation. They also prevent fuel from forming sticky resins that can ruin a carburetor.

If you don't use a fuel stabilizer, fuel can form sticky resins that can quickly ruin a carburetor. Chemical reactions within stored fuel, plus the evaporation of some volatile components, can leave liquid fuels less likely to ignite properly in an engine after more than three months of storage. Old fuel can also leave gummy deposits behind in sensitive areas of the motor.

STA-BIL® Fuel Stabilizer, for example, provides a sacrificial molecule to the oxidation process, allowing oxygen to attack the STA-BIL® molecule and not oxidize gasoline. However, the components of STA-BIL® will begin to oxidize over time, diminishing its capability to continue providing effective protection to stabilized gasoline.

Therefore, if you don't use a fuel stabilizer, you risk engine problems that can reduce fuel efficiency or even cause engine failure.

How do you use stabilized fuel?

Using a fuel stabilizer is a great way to preserve the fuel in your tanks and keep your various motors running smoothly. Here is a step-by-step guide on how to use a fuel stabilizer:

Step 1: Add Measured Stabilizer to Tank

Read the product instructions on the brand of stabilizer you've purchased. Make sure your vehicle's tank is nearly empty. Once you've done this, measure the correct amount of stabilizer and pour it into the tank.

Step 2: Fill Your Tank with Fuel

Fill your tank with fuel. This disperses the fuel stabilizer with gasoline and ensures that your tank is minimally exposed to air or water. For best results, opt for an ethanol-free type of gas.

Step 3: Run the Engine

Run the engine for 5-10 minutes to allow the fuel stabilizer to reach the entire fuel system.

For everyday life, fuel stabilizers aren't necessary. Fuel stabilizers are most useful for seasonal equipment, classic cars, or boats that tend to sit for more than three weeks at a time.

While the lifespan of fuel stabilizer varies depending on the brand, most mixtures will preserve fuel for a full year. STA-BIL Storage, for example, keeps fuel fresh for up to 24 months.

Yes, most fuel stabilizers are designed to work with all grades of gasoline, including gasoline that contains ethanol. However, always check the product label to be sure.

While a stabilizer can extend the shelf life of gasoline, it doesn't last indefinitely. Generally, stabilized gasoline can be stored for up to 12 months, but it's best to use it within 6-8 months for optimal performance.

What are the best stabilized fuel brands?

When it comes to the best brands of stabilised fuel, STA-BIL is the most frequently mentioned. The brand has been around for over 60 years and is known for its fuel stabiliser, which is a great choice for long-term storage. STA-BIL's fuel stabiliser keeps gasoline fresh for up to 24 months and is safe for 2- and 4-stroke engines. The brand also offers a diesel fuel stabiliser, which is specifically designed for diesel engines.

Another top brand is Star Tron, which offers an enzyme fuel treatment that is highly concentrated, with one ounce treating 16 gallons of fuel. This formula will stabilise gasoline for up to two years and can be used for 2-cycle engines.

Other notable brands include:

• Sea Foam: SF-16 Motor Treatment stabilises diesel and gasoline for up to two years.
• Lucas Oil: 10303 Fuel Stabiliser prevents fuel degradation and the harmful effects of ethanol.
• Yamaha: ACC-FSTAB-PL-32 Fuel Stabiliser & Conditioner works for both 2- and 4-stroke engines.
• Royal Purple: 11722 Max Clean Fuel System Cleaner and Stabiliser improves horsepower and fuel economy by up to 3%.
• Berryman: Total Fuel Stabiliser is compatible with all 2-stroke and 4-stroke engines.
• ISO-HEET: Water Remover is a fuel-line anti-freeze that absorbs up to five times the water of regular gas dryers.
• STP: Ultra 5-in-1 Fuel System Cleaner is formulated for modern engines and helps remove harmful deposits.

Frequently asked questions