Leaving old gas sitting in a string trimmer may cause it to develop starting and running problems. It’s important to not only use fresh gas, but you must also know how to store it and mix it properly to avoid carburetor and engine issues.

ECHO string trimmers use a gasoline and oil mixture at a ratio of 50:1. 50 parts unleaded gasoline with a minimum octane rating of 89 and a minimum ethanol content of 10% is mixed with 1 part premium 2-cycle engine oil.

Keep reading to learn more about the importance of using the correct fuel in your ECHO trimmer. I include information on the effects of ethanol on your trimmer; how to mix 2-cycle oil and gas; and why a fuel stabilizer is needed.

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Follow all safety instructions provided in your equipment operator’s manual prior to diagnosing, repairing, or operating.Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.

Old or Bad Gas in an ECHO String Trimmer

It’s not good to let an ECHO string trimmer sit around with fuel in the fuel tank. This is because gas begins to break down as soon as 30 days after purchase.

Ethanol, an alternative environmentally-friendly fuel added to most gasoline, attracts moisture from the air. When this ethanol and water mix evaporates, a sticky substance is left behind that coats the fuel components.

This can clog the fuel system and cause premature corrosion. Old fuel is a common reason you may experience carburetor failure.

Because gas begins to go bad so quickly, it’s important to use fresh gas and consume it within 30 days. If you are unable to consume it this quickly, add a fuel additive like Sea Foam Motor Treatment.

This product will stabilize your gas and reduce moisture so it lasts a little longer. You can also check to see if the oil you add to the gas has a long-term stabilizer. (Read the label: fuel stabilizers added to oil can last anywhere from 30 days to up to 2 years).

ECHO string trimmers require unleaded gasoline with a minimum octane rating of 89 and a maximum ethanol content of 10%. Mix a 2-cycle premium oil with the gas before adding it to the fuel port.

Avoid gasoline that includes ethanol contents greater than 10% including fuels sold as E15, E30, and E85. These fuels contain up to 15%, 30%, and 85% ethanol respectively.

Ethanol-free fuels are best and will reduce the issues you experience due to old fuel. Ethanol-free fuels can be found at your local hardware store or online. ECHO branded 2-cycle Red Armor Premix or 2-cycle TruFuel 50:1 Premix are two good options.

They can also be found at select fuel stations sold as recreation fuel (REC-90). Look for a fuel station near you at pure-gas.org.

Gas and Oil to Use in a 2-Cycle ECHO String Trimmer

2-Cycle Gas and Oil Mix in an ECHO String Trimmer

ECHO string trimmers require a 2-cycle premium oil to be mixed with gas before filling the fuel tank. Don’t make the mistake of adding straight gas to your 2-cycle string trimmer. You will regret this decision.

Gas runs extremely dry so adding straight gas will cause the engine to seize. Without the lubrication provided by the addition of oil to the gas, the internal parts of the engine won’t be able to move freely.

Most likely, if you accidentally add straight gas to your ECHO string trimmer and start it, you will have to replace it with a new one. The engine will be damaged.

ECHO 2-cycle string trimmers use a gas and oil mixture at a ratio of 50:1. This means you must mix 50 parts gas with 1 part oil. Refer to the chart below for the amount of oil required to be mixed with common gallon measurements.

When creating this mix, use unleaded gasoline with a minimum octane rating of 89 (mid-grade) and maximum ethanol content of 10%. Add a 2-cycle premium oil that is ISO-L-EGD and JASO M345 FD certified. Note: 2-cycle engine oil is NOT THE SAME as regular engine oil.

How to mix gas and oil for a 2-cycle ECHO string trimmer:

• Use the chart below to determine how much fuel mix to prepare.
• Remove the cap from an approved gas can. Add unleaded fuel (minimum 89 octane rating & maximum 10% ethanol content) to a gas can.
• Refer to the chart below for the ounces of oil required. Add the 2-cycle oil to the gas can.
• Replace the cap.
• Gently shake the fuel and oil until they are mixed.
• Add to the ECHO string trimmer’s fuel tank.

You can use the manufacturer’s recommended oil ECHO Power Blend or ECHO Red Armor. Another alternative is this 2-cycle mix by Kawasaki. It comes in 5.2 oz. and 6.4 oz. bottles that can be mixed with 2 gal. or 2.5 gal. of gas respectively for a 50:1 mix.

Using one of these brands of oil that already includes a fuel stabilizer helps extend the life of the gas and oil mix. Just read the bottle. Some fuel stabilizers are good for 30 days while others are good for up to two years. You can also add a stabilizer like Sea Foam Motor Treatment.

2-Cycle ECHO Gas to Oil Mix

2-Cycle Premixed Ethanol-Free Fuel for an ECHO String Trimmer

The best type of fuel to use in an ECHO string trimmer to reduce fuel problems and extend engine life is an ethanol-free fuel mix. This is an ethanol-free blend of oil and fuel that is ready to pour into your ECHO string trimmer’s fuel tank.

You won’t have to deal with the bad effects of ethanol as discussed in the fuel section. Products that work well are ECHO Red Armor and TruFuel 50:1 premixed fuels.

In Summary

The fuel used in your ECHO string trimmer not only affects performance but also affects the likeliness problems develop in the fuel system and engine. Follow these simple tips when choosing a fuel for your string trimmer:

• Always use fresh gas.
• Make sure the gas contains no more than 10% ethanol.
• Choose gasoline with a minimum 89-octane rating.
• Use a 2-cycle gas and oil mixture at a ratio of 50:1.
• Add a fuel stabilizer so your gas lasts longer without breaking down. Not all stabilizers last the same length of time. A stabilizer like Sea Foam Motor Treatment will stabilize fuel for up to 2 years.