Fuel is oftentimes the problem causing a string trimmer to not start, run sluggishly, or lose power. Choosing the best gas and knowing how to care for that fuel will help minimize problems in the fuel system or engine.

Shindaiwa string trimmers use a gasoline and oil mixture at a ratio of 50:1. 50 parts of 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 Shindaiwa. 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 a Shindaiwa String Trimmer

Most types of gasoline contain ethanol. This is usually a corn-based fuel to make gas more environmentally friendly. It is a product that may be better for the environment but isn’t good for the small engine on your Shindaiwa string trimmer.

Ethanol attracts moisture from the air. This moisture and water mixture causes premature corrosion and can be very harmful to the engine when it separates from the gas and burns extremely.

It can also leave behind varnish and gummy deposits that can clog the fuel system.

Because gas will start to go bad as soon as 30 days after purchase, it’s important to use fresh gas and consume it within this time. 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 make sure the oil you add to the gas has a long-term stabilizer. (Read the label: some only last 30 days).

Shindaiwa 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. 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

Ethanol-Free Fuels for Shindaiwa String Trimmers

• ECHO 2-Cycle Red Armor Premix
• 2-Cycle TruFuel 50:1 Premix

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

2-Cycle Gas and Oil Mix in a Shindawa String Trimmer

Shindaiwa string trimmers require a 2-cycle premium oil to be added to 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.

Doing this will cause the engine to seize up and no longer run. This is because gas runs very dry. 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 string trimmer and start it, you will have to replace it with a new one. The engine will be damaged.

Your Shindaiwa 2-cycle string trimmer uses a gas and oil mixture at a ratio of 50:1. This means 50 parts gas is mixed with 1 part oil. Refer to the chart below. 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.

How to mix gas and oil for a 2-cycle Shindaiwa 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 Shindaiwa 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 Shindaiwa Gas to Oil Mix

2-Cycle Premixed Ethanol-Free Fuel for a Shindaiwa String Trimmer

The best type of fuel to use in a Shindaiwa 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 Shindaiwa 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 Shindaiwa 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 Shindaiwa 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.