How-To: Stabilize Your Generator’s Fuel For Storage

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What is the one thing that it seems that most of us just simply don’t remember to do EVERY single time we store our generators? If you’re anywhere near as absent-minded as myself, the answer is forgetting to treat the fuel in your home generator, the one essential tool that can keep your lights on in an emergency.

Untreated fuel is responsible for many hours of frustrated pull-start attempts, denial about bad fuel, and eventual carburetor cleaning or replacement. Don’t allow yourself to become a victim of bad gasoline, be sure to treat the fuel in your generator before putting it in storage or winterizing.

It’s the only way to ensure that your generator starts when you REALLY need it to. 

Adding fuel stabilizer to your generator before storage or putting it away for the winter will prevent you from wasting fuel by running it dry.

Instead, just add fuel stabilizer and be ready in a moment’s notice. If you let the fuel system run dry, trying to start it again the next time will be a pain. Using a quality fuel stabilizer will help your generator turn over on that first crank when you need it the most. 

When you add fuel stabilizer to your generator, it can help prevent internal rust and corrosion to the fuel tank and damage to the fuel system. Gas can begin to break down after around 30 days of sitting in the tank without fuel stabilizer. This leads to clogged carburetors, rotting fuel lines and generally just making a big mess of everything.

A carburetor clogged with varnished fuel

Why does fuel need to be treated?

Ethanol content in today’s gasoline has been causing endless issues with fuel storage, where you’ll run into problems such as:

  1. Varnishing
  2. Breaks down chemically
  3. Doesnt start
  4. Gums up the carburetor
  5. Rots fuel lines

In diesel fuel, the main enemy is water.

Water in diesel fuel causes issues such as:

  1. No start conditions
  2. Diesel engine stalls out
  3. Injector damage
  4. Complete fuel system overhaul sometimes required

Best Fuel Stabilizers For Gasoline Generators

We have complied and ranked experiences and reviews from the top brands of fuel stabilizers. Our aim is to bring you the most comparison information available, so that you are able to choose the best additive to buy and add to your generator’s fuel tank before storing it.

1. STA-BIL Fuel Stabilizer

If you have ever pulled a start cord, there is little doubt that you have likely heard of STA-BIL. Especially if you’ve stored your engine with gas in the carb for some time, allowing the gas to gum up and keep it from running. Now you’re back to pulling that cord, over and over.

There’s always a neighbor, relative of friend who will be sure to ask if you remembered to put stabilizer in the fuel, after your engine fails to start. The first name they mention will most likely be STA-BIL. With good reason, as the STA-BIL brand has for some time been one of Americas #1 fuel stabilizers.

STA-BIL has some great attributes that help to keep fuel stable for long periods of time. Some of it’s best features are:

  • Long term storage ability keeps fuel fresh for up to 24 Months
  • No need to drain and waste fuel when storing your generator
  • Prevents gasoline from gumming up and varnishing, making starting much easier
  • Works for all types of gasoline, even ethanol loaded gas
  • Works for 2-strokes and 4-strokes, universal solution for just about any gas powered engine

Dosage Guide For STA-BIL

STA-BIL comes in a multitude of different sizes to treat just about any fuel stabilizing need that you have. Starting from the teeny-tiny 4oz blister pack, the sizes range all the way up to a gigantic 1 gallon bottle.

Looking at the normal uses for STA-BIL you will find that the 16oz and 32oz sizes are the most popular, as they are a good balance between individual doses and shelf life. The amounts used to treat gasoline are:

  • 1/2 ounce of STA-BIL to treat 1 gallon of gasoline
  • 2oz of STA-BIL treats 5 gallons of gas
  • 6oz of STA-BIL to treat 15 gallons
  • 10oz of STA-BIL can treat 25 gallons
  • 16oz is the amount to treat 40 gallons

As you can see by the usage chart, STA-BIL is a highly concentrated fuel additive that will go a long way in treating all your fuel system needs.

Keeping it’s concentration and effectiveness in mind, there is a downside to storing STA-BIL (and pretty much any other fuel stabilizer) and that is that they use a sacrificial molecule to actually suspend the oxidation process of gasoline. Oxidation will actually attack this molecule before it has a chance to varnish your gasoline.

Because of this, the shelf life of opened STA-BIL that has had the seal broken (but cap replaced and tight) and been exposed to air is about 2 years. Keeping this in mind, our recommendation is to purchase only the amount that you will need at a time. The good thing is that it can be used in any gasoline equipment that sits for extended periods of time, so a bottle of STA-BIL can be used up pretty quick!

2. PRI-G Fuel Stabilizer

Another great product that can be easily found in the generator and small engine scene is the PRI-G gasoline additive. This treatment will ensure your generator’s fuel system is cleaned up and stays free of any aged gasoline that could create a blocked passage. With it’s higher concentration, PRI-G can treat a higher number of gallons of gas per ounce compared to its competitors.

PRI-G has an impressive resume. Here we list some of its notable features and ways your generator’s fuel system will stay in tip top shape, or be revived from prolonged periods of storage:

  • Works with 2 and 4-stroke engines
  • Removes and protects against harmful deposits
  • Stabilizes fuel to prepare for storage
  • Revitalizes aged fuel to a reusable condition
  • Cleans and clears fuel lines and injectors
  • Reduces risk of water separation in modern ethanol gasoline

Dosage Guide For PRI-G

PRI-G comes in a few different sizes depending on your specific needs, use, or the size of your fleet. While the most common sizes are 16 oz. and 32 oz. bottles, PRI-G can be purchased in a container as large as 128 oz. (1 gallon). The amount of fuel each bottle can treat is as follows:

  • 16 ounces treats 256 gallons
  • 32 ounces treats 512 gallons
  • 128 ounces treats 2048 gallons

PRI-G treatment is capable of treating 16 gallons of gasoline per ounce of additive. With it’s handy measuring device built into the bottle, there’s no need to mess around with additional measuring equipment. Measurements in increments of 1/2 ounce, or 8 gallons of gasoline, can be easily made during use.

With it’s long shelf life, there’s no fear of having a bad product the next time you go to use it. The shelf life of PRI-G is indefinite while sealed, and up to 3 years after opening! While it’s said to have the capability of keeping gasoline fresh for many years, it is recommended to refresh your fuel after a year of sitting if you will be storing it longer than one year.

With it’s versatility and ability to retain and restore gasoline quality, there’s no question why PRI-G is a favorite from hobbyists to professionals. If you want something tough that you can rely on, PRI-G is the product for you!

3. Star Tron Enzyme Fuel Treatment

Star Brite has created another very affective and popular product in their Star Tron Enzyme Fuel Treatment. If you’re going to be storing your machine or fuel for an extended period of time, there’s no need to sweat. With their use of enzyme technology, they have built a treatment that is designed to give extra protection to your engine from the harmful effects ethanol in modern gas could create.

As with the other popular products, Star Tron Enzyme Fuel Treatment has many talents and is built to do more than simply protect against ethanol in gasoline. A list of the features includes:

  • Protection against ethanol water separation in gasoline
  • Stabilizes fuel to prepare for storage
  • Restores aged gas to a useable state
  • Enhances combustion in gas for better performance and less deposits
  • Cleans deposits from engine and fuel system

Dosage Guide For Star Tron

Star Tron Enzyme Fuel Treatment comes in a variety of different sizes for you to choose from. One of the things we like about this product is the larger selection. For the majority of generator owners, this usually means a smaller gas tank. This is where the additional sizes and a lower concentration may be the right choice for you. Below is a list of the various sizes as well as the number of gallons each bottle can treat:

  • 8 ounces treats 48 gallons
  • 16 ounces treats 96 gallons
  • 32 ounces treats 192 gallons

This treatment is capable of treating 6 gallons of gas per 1 ounce of additive. Star Brite had a few tricks up their sleeve as well when they developed their clever bottle. Not only is the bottle clear you can see the liquid level, it also has a scale on the side of it so you can measure the amount of liquid you are using without having to pour it in another measuring device! This is convenient if you are using the additive on the go as well as simply making it more efficient at home.

Star Tron Enzyme Fuel Treatment will let you sleep better at night knowing your equipment will be covered for an extended period of time. It has an impressive ability to stabilize gas for up to two years! While we have primarily covered the standard version of this fuel treatment for the purposes of our generators, Start Brite also has a line of additional additives in a concentrated and super concentrated formula that may also fit your needs.

With it’s dependability and practical lineup, its easy to see why so many people choose to protect their machines with Star Brite’s products. Be sure to check their lineup out and get your generator protected today!

Best Fuel Stabilizers for Diesel Generators

So you say you have a diesel generator? No problem! Just like gasoline generators, there are plenty of additives for diesel generators as well. We have listed our top 3 favorites based on their performance, characteristics, and experiences and have written a little bit about them to help you choose the right one for your application.

1. PRI-D Complete Diesel Treatment

Power Resource Inc. did such a good job with their gasoline counterpart, they also developed a top of the line diesel treatment in their PRI-D product. If you have a diesel generator, and store additional diesel for emergencies and extended use, then PRI-D is a must see product for you. Similar to their other products, PRI-D has a higher concentration when compared to its competitors. This will guarantee the best treatment of the toughest diesel fuel and insides of your generator for years of healthy operation.

We were impressed with not only the features of PRI-D, but the positive experiences had by those who use it. Some of the standout features delivered to your generator and the fuel that power it can be found below:

  • Removes and protects against harmful deposits and carbon buildup
  • Stabilizes diesel fuel to prepare for storage
  • Revitalizes aged fuel to a reusable, refinery condition
  • Cleans and clears fuel lines and injectors
  • Can also be used in kerosene for maximum versatility

Dosage Guide For PRI-D

PRI-D also comes in a few different sizes depending on your specific needs, use, or the size of your fleet. While the most common sizes are 16 oz. and 32 oz. bottles, PRI-G can be purchased in a container as large as 128 oz. (1 gallon). The amount of fuel each bottle can treat is as follows:

  • 16 ounces treats 256 gallons
  • 32 ounces treats 512 gallons
  • 128 ounces treats 2048 gallons

PRI-G treatment is capable of treating 16 gallons of gasoline per ounce of additive. With it’s handy measuring device built into the bottle, there’s no need to mess around with additional measuring equipment. Measurements in increments of 1/2 ounce, or 8 gallons of gasoline, can be easily made during use.

With it’s long shelf life, there’s no fear of having a bad product the next time you go to use it. The shelf life of PRI-G is indefinite while sealed, and up to 3 years after opening! While it’s said to have the capability of keeping gasoline fresh for many years, it is recommended to refresh your fuel after a year of sitting if you will be storing it longer than one year.

With PRI-D’s proven capability and abilities to handle the worst conditions your diesel fuel will encounter, it’s a sure bet you won’t be disappointed. Make sure to pick some up today and give your generator the treatment it deserves!

2. STA-BIL Diesel Fuel Stabilizer and Performance Improver

Best diesel additive

We’ve already talked about how STA-BIL is one of America’s favorite fuel stabilizers, and there’s a reason for that! Fortunately, for those who have diesel generators, STA-BIL has created a product specifically for diesel fuel as well.

  • Prevents rust and corrosion from forming
  • Keeps Diesel fuel fresh for up to 12 months while storing
  • Prevents sludge and sediment from building up
  • Reduces oxidation of diesel fuel

Dosage Guide For STA-BIL Diesel Fuel Stabilizer and Performance Improver

STA-BIL comes in a multitude of different sizes to treat just about any fuel stabilizing need that you have. Starting from the teeny-tiny 4oz blister pack, the sizes range all the way up to a gigantic 1 gallon bottle.

For the diesel version of STA-BIL additive, you will find that the 32oz and 128oz (1 gallon) sizes are the most popular, as they are a good balance between individual doses and shelf life. The in-season amounts of diesel the bottles are capable of treating are:

  • 32 ounces treats 320 gallons
  • 128 ounces treats 1280 gallons

While using STA-BIL in-season, 1 ounce is capable of treating 10 gallons of diesel fuel. For storage use, it is recommended that 1 ounce is used to treat 5 gallons of diesel for maximum protection. STA-BIL has designed a handy two-cap bottle that will make your life easier as you maintain your equipment. It has a nice measuring device at the top of their bottle which will make using it a breeze for small fill-ups. For larger applications, they also have a second lid and scale on the side of the botte to simply pour the fluid out without the need to use smaller device.

There’s no need to fret while storing your fuel and generator while it waits to be used as STA-BIL Diesel Fuel Stabilizer will keep your fuel fresh for up to 12 months! After that, simply add more if needed to keep it fresh for another 12 months.

3. Lucas Fuel Treatment

Lucas Diesel Additive

Lucas Upper Cylinder Lubricant is specially made with a blend of super slick oils and additives with a detergent action. Not only will it keep your diesel fuel in tip top shape, it will also service your generators engine and components to keep them in good condition for years to come. With the abuse your generator takes both from running for hours at a time, and sitting for weeks, months, or even years at a time, Lucas Upper Cylinder Lubricant is a good choice to keep the insides of your generators engine fresh.

Since Lucas Upper Cylinder Lubricant has a few additional features to offer, we summarized it in the list below:

  • Lubricates engine internals such as rings, cylinder walls, and valves
  • Lubricates and cleans fuel pumps and injectors
  • Neutralizes low sulfur diesel fuel
  • More efficient fuel burn for increased power and less fuel consumption

Dosage Guide For Lucas Fuel Treatment

Depending on the size, quantity, or need for servicing generator diesel, Lucas Fuel Treatment also comes in a few different size options to make your life easier. If you’re simply a hobbyist or don’t require attention to a large amount of fuel, this treatment comes in containers as small as 5.25 ounces to treat a modest 25 gallons of diesel fuel. For the more serious generator owner, Lucas makes containers up to 128 ounces (that’s an entire gallon!) to treat up to 400 gallons of fuel.

Below you can find the bottle sizes along with the number of diesel fuel they treat:

  • 5.25 ounces treats 25 gallons
  • 32 ounces treats 100 gallons
  • 128 ounces treats 400 gallons
Lucas Fuel Treatment Measurement

Lucas Fuel Treatment is capable of treating slightly over 3 gallons of diesel fuel per ounce of treatment. With the design of their bottle, adding Lucas Fuel Treatment to your generators system is quick and clean. The smallest bottle contains a slim neck to allow for the bottle to be inserted into the opening of the fuel system to eliminate spills. The 32 ounce bottle is built with a cone shaped exit to easily aim and squirt the treatment with no spills, and also features a measuring gauge on the side of the bottle so you know exactly how much you are using.

It’s recommended to add Lucas Fuel Treatment to your generator each time you fill it with diesel. This will help condition your generator as you run it. Having this additive in your diesel means giving your fuel injectors, cylinder walls, valves, fuel pump, and combustion chamber a good cleaning and prevention of harmful buildup. On top of that, an added benefit is the lubrication traits that Lucas Fuel Treatment has that will keep the internal components moving freely with minimal friction that could be harmful to your generators engine.

It’s no wonder so many people choose Lucas Fuel Treatment with all of it’s unique features that stick out from the competition!

Final Thoughts

We understand it can seem overwhelming to select the proper additive for your application. Whether you are looking to store your generator, or simply give the insides a good cleaning, we hope this guide has helped! Regardless of what you choose, your machine will be sure to benefit from giving it the extra protection it needs. Make sure you spend the minor amount of money to keep your investment protected and running at peak performance. Your generator is there when you need it, so make sure you return the favor!

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