Type of Gas for Weed Eater?

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A weed eater that runs on fuel requires extra care and attention as compared to those that run on electrical power. This is largely because of the regular refueling and maintenance work needed to ensure the weed eater functions properly. If you own one of these devices, you may be wondering whether you can just use regular gas as fuel for your unit. Read on below and discover the right type of fuel that will give you great results and keep your lawn tool working well for a long time.

Some weed eaters use a mixture of oil and gas, while others have separate reservoirs for these two essential fuels. Thus, it is extremely important to ensure you are refueling your handy maintenance tool with the proper fuel. This will prevent engine damage as well as guarantee the durability and longevity of your weed eater.

Take notice to the cap on top of the fuel reservoir. If it says ethanol 10% fuel, then it is okay to use regular unleaded gas with ethanol. Otherwise, ethanol is not good for the carburetor and fuel lines. It will cause it to gum up quicker and require a carburetor and fuel line change if it sits for a long period of time, like during the winter months. Then the entire carburetor and fuel lines will have to be replaced. More on this below about ratios.

Fuel injector cleaner will not help at this point. Carburetor and fuel line kits are cheap to acquire on Ebay. Craftsman and Poulan are the most popular, and some do work interchangeably. Just make sure you get the right kit that matches the type you have.

Determining the Best Ratio of Gas and Oil

A weed eater requires both oil and gas to maintain proper lubrication in the piston and crankshaft. Additionally, for optimal engine functioning, the engine oil and gas must be mixed in the correct ratio to avoid problems. For example, large amounts of oil in the engine can cause too much exhaust smoke, while inadequate oil causes overheating, insufficient power and eventual engine damage.

All brands of weed eaters usually use a 40:1 ratio, which is the same as 1 US gallon of unleaded gasoline to 3.2 ounces of engine oil. The unleaded gas used in the mixture should consist of 87 octanes. Additionally, do not use regular motor oil for the mixture as it has noncombustible additives that have the potential of significantly damaging the internal engine of your weed eater.

The gasoline used in a weed eater should strictly contain less than 10% of alcohol. Excessive alcohol content in gas can destroy most parts of the fuel system, including the fuel lines. This will cause the trimmer’s engine to run much hotter, which will result in vapor locking and engine stalling issues. Additionally, also ensure you are not using unmixed gasoline since oil serves an important part of ensuring efficiency and lubrication during operation.

If you are having trouble remembering all this information on the right oil to gas ratio, then you should know that it is normally clearly listed on the fuel tank or gas cap of your weed eater. You can also check the product manual as it will likely have the information on what amount of gas and oil you need for optimal engine function. Reading all of these different sources can give you a better idea when it comes to refueling your weed trimmer.

Signs That Are Using the Wrong Gas and Oil Ratio

At times it is possible to get confused and mix the wrong ratio of gas and oil. Even though you have done a mistake, you can still rectify that problem and save your weed eater’s engine from breaking down. The following are a few signs that you should look out for if you are not sure that you have refueled with the right amounts of gas and oil.

  • Overheating
  • Excessive smoke
  • Reduced overall efficiency
  • Engine splutters and stops

If you notice any of these issues after refueling your weed eater, then you need to stop the machine and change the fuel.

How to Create the Right Gas and Oil Fuel Mixture

Refueling your weed eater is a simple process that will be explained briefly here below. Nevertheless, you must have the following key things before starting the refueling process:

  • 1 gallon container
  • A measuring jar or cup
  • Properly formulated 2-cycle oil
  • Gasoline

Start by looking for a clean and empty, one gallon container. Next, begin the mixing process by first pouring the right quantity of engine oil into the container. Gradually add gasoline into the container while swishing the mixture around for better mixing. The container you choose should have enough room so that it accommodates the mixture of gas and oil. Make sure you agitate the container again every time you want to refuel.

A common mistake that most weed eater owners make is to assume that they can just mix the oil and gas in the device’s gas tank. This should be avoided at all costs as you are more likely to prepare the wrong ratio, not to mention the fact that you will not get a comprehensive blending. Also, ensure that you are using fresh fuel that you plan to completely exhaust within a month.

Once you have prepared your fuel mixture, you are now ready to refuel your weed eater. Prepare a safe and clean area where you can do this task to prevent fuel spills. Start by unplugging the spark plug and then open the trimmer’s fuel tank. Next, take out any fuel remaining in the tank by overturning your weed eater.

Now take the fuel mixture that you had prepared earlier and refuel your weed eater. Make sure to do this part very carefully since fuel is generally quite expensive and thus you should not spill it around the tank. Once you have filled up the tank to the desired level, lock the gas tank and use a damp cloth to remove any remaining fuel around the area.


In the same way as food is essential for the healthy functioning of the human body, so is fuel critical for a weed eater. It is up to every owner to take responsibility of maintaining the engine of their convenient trimmers if they are to work properly and last longer. This can be done easily through ensuring the right ratio of gas and oil is used as well as the right type.

Special care must also be observed during the fuel preparation and changing processes. Making the wrong step can cause the engine to develop problems that could cause you a lot of money in repair costs. This is where your product manual and all the information listed above can help you out in guiding you on the correct way to change your fuel.

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