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This is the Type of Gas Lawn Mowers Use

When spring starts knocking on the door, every homeowner knows the headache of breaking out the lawn equipment and getting it ready for the season, especially the lawn mower. But many are left scratching their heads at the gas pump because they aren’t sure what type of gas their lawn mower is supposed to use!

Lawn mowers use unleaded gasoline with a minimum octane rating of 87 and an ethanol content of 10% or less. This type of gasoline can be easily found at the local gas station sold as regular or E10 gas.

Whether you have owned a lawn mower for years or are just now purchasing one, you will want to learn more about the care of this equipment. Proper care will lead to a much longer life for your mower. To learn more about which gas to use and how to care for your lawn mower, keep reading. 

4-stroke (4-cycle) engines use a straight gas. When finding fuel for a 2-stroke (2-cycle) engine, read my article “This is the Gas to Use in a Push Mower” to find fuel requirements for a 2-stroke engine.

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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, knowledge or are not in the condition to perform the repair safely.

What is the Best Gas for Lawn Mowers?

Those with all sizes of yard rely on a lawn mower to cut their grass and create a yard they are proud of. While lawn mowers come in different sizes and styles, they are all relatively similar when it comes to the internal components.

Most lawn mowers will feature the same four-stroke engine style, which uses unleaded gasoline. 

While most lawn mowers use unleaded gasoline, some will require other styles of gasoline, and it is critical that you look over your manufacturers’ guide to see what works best for your lawn mower.

However, if you are using any major brand lawn mower that has a 4-cycle engine, traditional unleaded will be the best choice. 

Some things to keep in mind when purchasing fuel for your lawn mower:

  • You should always purchase fresh gasoline. Never let gasoline sit for weeks before using and never allow it to get mixed with water if stored outdoors.
  • Most choose a gasoline octane of 87 or more for their lawn mowers. 
  • You should try to get gasoline with a lower ethanol content. If gasoline in your area has over 10% ethanol, you may want to purchase elsewhere.

I will further break down how to choose your gasoline and why these key components are important. 

Choosing Gas for Your Lawn Mower

When purchasing a lawn mower, the first thing you must realize is regular refueling is a must. Similar to a car, your lawn mower simply will not run without being filled with gas regularly. The fuel used is vital to extending the lifetime of the mower and ensuring it runs smoothly.

Here are some tips to ensure you are buying quality gas for your lawn mower:

Always Buy Fresh Gas for Your Lawn Mower

One of the absolute most crucial steps to ensuring you are using quality gas is to always refill your mower with fresh fuel. 

The problem is that many will fill up a plastic gas can for their mower and allow this to sit for long periods of time. When left outside, this gas is subject to the elements and can become less potent or even ineffective over time. 

The best option is to always get gas prior to mowing and ensure that you use the gas you have purchased quickly. You will want to get your gas from a larger, well-known gas station.

This ensures that the gas you are choosing is of higher quality and often fresher than smaller gas stations may offer.

Avoid High Amounts of Ethanol in Your Lawn Mower Gas

Ethanol, a corn-based product added to most gasolines, works well in our cars and trucks, but can be damaging to the small engines in our lawn mowers. Ethanol is corrosive to the lawn mowers fuel system.

Ethanol-based gas attracts moisture from the air and when the gas begins to breakdown, the water and ethanol mixture will sit at the bottom of the fuel tank.

Running this solution can cause your lawn mower to run extremely hot causing your engine to overheat and experience significant engine damage.

Purchase High Quality Fuel for Your Lawn Mower

Buying more expensive unleaded gas is not always the best, but I do highly recommend purchasing ethanol-free fuel as this doesn’t damage your fuel system like gas with ethanol does. This type of gas can be found at the pump at fuel stations or in canisters at your hardware store.

Recreation fuel (REC-90), an ethanol-free fuel, is sold at select gas stations. It can be up to $3.00 per gallon more expensive than regular gas. You can find a list of fuel stations in the United States and Canada that carry that recreation fuel at puregas.org.

Canisters of 4-cycle fuel can be purchased at your hardware store or online. This is definitely the most expensive way to purchase ethanol-free fuel, but it is very convenient.

If you are running a small lawn mower or smaller handheld equipment, this is a great convenient option to have sitting on your shelf.

If you buy higher-end gas and worry you will not use all of it, there are some ways to keep gas fresh. The best way to store gas is adding an additive to stabilize your fuel.

Here are a few tips when storing gasoline:

  • Use a plastic gas can that is designed for unleaded gas. Other types of plastic containers can break down.
  • Add a fuel additive to stabilize your fuel while the fuel is fresh. Once your fuel begins to degrade, the additive is not able to reverse the process. I like a fuel additive called Sea Foam because it reduces moisture buildup, stabilizes and cleans your fuel system. Read more about the advantages of Sea Foam in my article.
  • Try to avoid buying more than a 30-day supply of gas. The quicker you use the gas, the better. However, it can be hard to know exactly how much you have in your tank and how much you will need with each mowing.
  • Always rotate the gas you store to use the oldest fuel first.

Once you get the hang of buying gas for your mower, it is relatively simple to know what you need and when you need additional gas. By adding a fuel stabilizer and routinely alternating through your gas, you will not waste expensive gasoline, and it will be well worth the price.

Don’t Overthink It

Truly refueling your lawn mower should not be a stressful process and is relatively simple, even for beginners. The basics to keep in mind are to simply:

  • Get fresh fuel
  • Use a stabilizer if needed
  • Avoid high ethanol percentages (>10%) 

If you have any questions concerning your lawn mower, the manufacturer’s guide is always a great place to start for additional help.