Can you Use too much Fuel Stabilizer in your Generator?

Can you Use too much Fuel Stabilizer in your Generator

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Though draining your generator’s fuel tank is the most reliable way to prevent fuel-related issues when in storage. But, draining a generator’s fuel tank means lifting a heavy unit, fuel spills, and the trouble of discarding the gasoline.

Instead, you can add a fuel stabilizer to the gas in your fuel tank and store your generator after a camping trip. A fuel stabilizer when added to fresh gas can extend its shelf life to up to three years.

However, one question beginnings have when using a fuel stabilizer is: How much fuel stabilizer to use? Can you use too much fuel stabilizer in your generator? 

In this article, we’ll answer all your questions from how much to add, top brands comparison, to the best way to add to prevent overuse. But let’s start by looking at the basics of fuel stabilizers.

How does Fuel Stabilizer Work?

A fuel stabilizer is a petroleum-based additive that is used to extend the shelf life of gasoline for long-term storage. A fuel stabilizer, when mixed with gas creates a protective layer that prevents oxygen, water, or moisture from oxidizing gasoline. This keeps the gas fresh and retains its functionality.

The chemicals in the stabilizer prevent oxidation, neutralize water to prevent fuel separation while protecting the engine and fuel tank from corrosion. It also cleans the fuel system, carburetor and prevents them from the gum, varnish, and rust.

When poured into a fuel tank, this additive readily mixes with the gas, and running the generator for some time circulates the stabilizer throughout the system. A good fuel stabilizer is suitable for all types of gasoline, including ethanol-blended, ethanol-free, and mixed gas.

One thing to remember is a fuel stabilizer cannot revive bad and contaminated gasoline. However, it can work wonders when added to fresh fuel before storing your generator.

When to Use Fuel Stabilizer?

Generally, fuel stabilizers are for people who are planning to store their generators for the long winter or are not going to use them for an extended period. Adding a stabilizer will ensure your generator starts without any issue and prevent all fuel-related issues.

Fuel stabilizers are not for full-time RVers or RVers who go camping off the grid regularly. They are for campers who rarely camp in the wild or do so few times a year.

When a generator is used regularly, it burns through the fuel in the tank forcing you to refuel. This prevents the gasoline in the tank from degrading and going stale. 

However, for seasoned RVers, who go boondocking a few times a year, you have a generator sitting with fuel in storage for a few months in a row. For them, fuel stabilizers are the most inexpensive insurance to keep the powerhouse ready for the next trip and extend its working life.

Can you Use too much Fuel Stabilizer in your Generator?

Overusing fuel stabilizers is not necessarily bad until the fuel to stabilizer ratio becomes abnormal (like 1:1). However, adding too much fuel stabilizer doesn’t have any benefit either. It will not extend the functional life of the gasoline anymore by using too much fuel stabilizer.

Most brands have their recommendation on how much fuel stabilizer to use per gallon of gasoline or diesel. Brands like STA-BIL recommends 1 ounce of stabilizer per 2.5 gallons of gas, whereas, Seafoam recommends 1 ounce of fuel treatment per gallon of gasoline.

Though too much fuel stabilizer won’t hurt your generator, adding more than what’s required will add unnecessary cost. On the other hand, as you add more of the additive, you’re simply diluting the gasoline which will result in loss of power from the engine.

Therefore, I highly recommend reading the manufactures guideline before adding the fuel stabilizer to your gasoline. Why add extra and increase the cost when the recommended quantity of stabilizer can do the magic.

Stabil vs Seafoam: Which is Best for your Generator?

Seafoam is a multifunctional product that offers the benefit of both a fuel stabilizer and fuel treatment. On the other hand, Stabil is a fuel stabilizer that only works to keep gasoline fresh in storage for extended periods.

Both Seafoam and Stabil have similar functionality when thinking about extending the shelf life of fuel. But which one is right for you?

Let’s take a look at some of the differences between Seafoam vs. Stabil.

STA-BIL Fuel Stabilizer

Stabil (Buy at Amazon) is the first name that comes to mind when talking about fuel stabilizers. Its primary and only function is to preserve the fuel and prevent it from degrading.

It is a glycol-based additive that is similar to antifreeze which means it forms a thin blanket on top of the fuel. This blanket seals the fuel and becomes a barrier between the fuel and moisture.

Because of how it works, fuel that is stabilized with Stabil cannot be shaken, as it increases the risk of the thin film breaking. Once broken, the film or blanket will not reconnect, making it easy for moisture to damage the fuel.

This makes Stable a bit risky to use with small generators that may have to move. However, the film or blanket formed by Stabil is strong enough that the fuel inside your generator or container needs to move vigorously for the layer to break open.

Stabil works with all types of gasoline, be it ethanol-blended or ethanol-free, but is not designed for diesel. It can keep the gas in your tank preserved for over 24 months and costs less compared to Seafoam.

Seafoam Fuel Treatment

Seafoam (Buy at Amazon) is a fuel treatment or detergent that is designed to provide two benefits in a single package. Firstly, this petroleum-based product works to fight fuel degradation by removing water or moisture from the fuel.

Secondly, it works to clean the internal components of your generator including the fuel system and the engine when the engine is run. This removes any residue, gums, or varnishes that may have accumulated over time.

Because Seafoam is a petroleum-based product, it mixes and combines with the fuel in your tank, unlike Stabil, which forms a separate layer on top. That means you don’t have to worry about exposing the fuel to moisture if the fuel in your generator is moved vigorously.

Like Stabil, Seafoam also offers protection for up to 24 months and works for both gasoline and diesel-powered motors. However, Seafoam is not as cost-effective if you only use it as a fuel stabilizer.

How to Add a Fuel Stabilizer to your Generator?

Adding a fuel stabilizer to your generator is as easy as buying one and adding the right amount. Then running your generator for 5-10 minutes to let the additive circulate throughout the system.

However, before adding the fuel stabilizer to the fuel tank of your generator, make sure the seal on the bottle of the additive is not broken. Moreover, if you’re using an old bottle of fuel stabilizer, make sure it hasn’t expired.

Generally, most fuel stabilizers sold in the market today last 2 years once the seal is broken. Broken down or expiring fuel stabilizers will usually have a darker shade of their original color.

Now determine the quantity of fuel in your tank to calculate how much stabilizer to use. Generally, 1 ounce for every 2.5 gallons of gasoline is recommended by most brands (read the bottle label on the brand you select).

Add the required quantity of stabilizer to the tank and then pump fresh gas in. This will help mix the gasoline and additive well compared to adding it after refueling. Make sure you fill up the gas tank to its recommended level to reduce the amount of air in the tank.

Now all you have to do is to run the generator for 5-10 minutes to let the additive circulate through the fuel system of your generator. You should now have a generator that is completely protected for up to 2 years and ready for the long winter storage.

How Long does Gasoline Last with Stabilizer?

A fuel stabilizer when added to fresh gasoline can preserve and retain its functionality from anywhere between 1 to 3 years. However, they are less effective when used with old gasoline and cannot revive degraded or separated gas.

Keeping the gasoline fresh in your generator in storage is not the most difficult task. All you need is a good fuel stabilizer and proper storage condition and your fuel should be good for multiple seasons.

Though fuel stabilizers are designed to work their best when used with fresh gasoline, they will not do any good if the fuel in your tank is already broken down. Make sure to add the stabilizer right after the fill-up before storage.


This brings us to the end of our article can you use too much fuel stabilizer. To be honest, using more than the recommended quantity of fuel stabilizers will not harm your generator but will also do no good.

Adding more stabilizers to your fuel tank won’t extend the shelf life from 24 to 48 months. However, the gas in your tank will dilute if the ratio of fuel to stabilizer goes overboard.

Therefore, I highly recommend following the manufacturer’s guidelines and using the quantity as instructed.