How to Mix Weed Eater Gas

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What do you think will happen if you run your car with the wrong fuel? Well, your car’s engine is likely to get damaged, which may cost you more money for repairs than you would have anticipated.

Similarly, a weed eater requires the right type of fuel as well as the right gas mixture for it to operate efficiently. Most weed eaters today are operated by a two-cycle engine, which requires a correct mixture of gasoline and oil to keep the piston and the crankshaft well lubricated.

Gas and oil should always be mixed in the correct ratios because too much oil can hurt the engine while too little oil can cause insufficient lubrication, which later ruins your engine’s moving parts.


Weed Eater Brands

Before deciding on the mix ratio you’re going to adhere to, you need to understand that weed eaters are available in different brands and models. Each mixing ratio depends on the model of the weed eater you own.

Among the common mix ratios you’ll get with most trimmers include 40:1 that converts to 3.2 ounces of oil to one gallon of gas, 32:1 which converts to four ounces of oil per gallon of gas, and 50:1 which is equal to 2.6 ounces per gallon of gas.


How To Mix Fuel

Step 1 – Check your string trimmer’s user manual.

Before you even touch anything, the first step to consider is reading the available user manual for your string trimmer. The reason for this is to allow you to understand the mixing criteria to avoid making any errors.

Secondly, a manual allows you to understand the exact type of engine your trimmer is using so that you can know how to mix the ratio between gas and oil. As mentioned above, each engine can differ slightly so you want to be totally sure you’ve got the correct ratio for YOUR model.

Step 2 – Get the right gas container.

Next, you have to check whether or not you’re using the right container for your machine. Most weed eaters come with specific containers that have been approved by the manufacturer. A good example of a perfect gasoline container is the no-spill fuel container that’s designed to reduce spillage and evaporation.

Step 3 – Choose the right gasoline type.

Next, consider choosing premium gasoline over regular gas for your weed trimmer. Choosing a cheap gas may prove fatal and might damage your engine in the long run. According to most weed eater manufacturers, using mid-grade unleaded gasoline is the best option.

The best octane rating for the best gasoline is 89. If your fuel has a lower octane rating, it will have a higher chance of overheating your trimmer’s engine, which may damage the machine. Make sure to double-check the alcohol concentration of the gas — it shouldn’t be more than 10%!

Step 4 – Choose the right oil.

Once you’ve sorted out the fuel type, make sure that you use high-quality two-cycle oils to protect your engine at the highest level. Different trimmers come with different engine capacities. If your model uses the 40:1 ratio of gas to oil, make sure that you mix 3.2 ounces of oil into one gallon of regular gasoline.

On the other hand, models that rely on the 50:1 ratio of gas to oil need a mix of 2.6 ounces of oil with one gallon of gas.

Step 5 – Mix the gas and oil.

Now that you’ve understood how to mix oil and gas in their correct ratios, let’s do this practically.

Start by pouring oil before adding gasoline. After you’re done, close the fuel canister tightly then mix the fuels vigorously.

Step 6 – Fill up your trimmer and get to work!

It’s now time to pour the fuel mixture into your trimmer’s gas cylinder. To do this, first, clean the fuel cap to prevent dirt from penetrating through when pouring the fuel.

Pour the fuel with the machine’s cap facing upward and your head not directly over the opening to prevent possible inhalation of fuel vapor. Always make sure that you shake the fuel canister a bit before refueling your trimmer to avoid any possible reheating or damaging of the engine.


Fuel Warnings

Just to mention, weed eaters should not use gasoline with an alcohol concentration of more than 10 percent. Too much alcohol in the gasoline can ruin some engine parts as well as cause the engine to overheat.

Also, using gasoline that hasn’t been mixed with oil can cause serious damages to the engine such as lack of lubrication that can make the moving parts such as the pistons to wear out quickly.


How To Mix Weed Eater Gas – FAQ

Do all 2-strokes need mixed gas?

Yes. All 2-cycle engines will need the gas mixed. The exact mix needed depends on the model and manufacturer recommendations, as mentioned above.

I mixed up my gas cans. How can you tell if oil was added to gas?

In a well-ventilated area, put a drop of that unlabeled gas onto a piece of plain white paper. If it’s only gas, it’ll dry back to white. If there’s oil in it, you’ll see an oil spot once it dries.

How can you tell if gas is bad?

The way your engine runs can tell you if the gas is bad. Assuming you have a well-adjusted carburetor in your weed eater, and it’s not a legitimate engine parts failure going on (i.e. a newer or well-maintained trimmer), you’ll know the gas is bad if it stalls, sputters, doesn’t start well, etc.

What happens if 2-stroke mix is wrong?

You’ll know. Extra smoke, oil leaking, and sometimes a sputtering engine are all signs that your mix is off. If this happens, empty the fuel tank and discard your mixed gas (safely!) and start over again.


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