Should I Use Ethanol Free Gas In My Lawn Mower?

The clear ethanol-free gas among the different kinds of gasoline may have piqued your interest. Or maybe, a landscape gardener suggested you use it in your lawn mower. Here is a straightforward explanation of why this could be a terrible or wise choice.

But before that, should I use ethanol-free gas in my lawn mower?

Quick Answer

The short answer is that you need to read your lawn mower instruction manual first. Most engines are specifically designed to operate with a particular gasoline type.

And since the fuel tank may not display an inscription or sign, you have to search for your lawn mower instruction manual online because using the wrong gasoline usually leads to engine damage.

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Why Should I Use Ethanol Free Gas In My Lawn Mower In The First Place?

The idea behind using ethanol-free gas in your lawn mower engine is to increase mileage and prevent corrosion.

Of course, when you put it like that, it sounds like the brightest idea, and it explains why most recent models basically suggest you use only ethanol-free gas in their tanks. But some newer models may make using ethanol-based gas a better, cheaper option.

The majority of old lawn mowers used leaded gasoline. With them, ethanol-free fuel should be your best option. But the most performant models with four-stroke engines may require lead-based additives to prevent preignition.

Ethanol-free gas has a positive impact on the carburetor. Above all, it does not come with the downsides of ethanol-laced gas.

To explain, E5, E10, and E15 gasoline contain bioethanol, which comes from renewable sources like corn, grains, and sugar beet. And even though ethanol blends are better for the environment, they cause corrosion in your carburetor when fuel sits in the tank for long periods.

To Switch Or Not To Switch To Non-Ethanol Fuel, That Is The Question

Small engines owners can benefit from using ethanol-based fuel in their lawn mowers. Why? Because ethanol gas:

costs less than ethanol-free gas
delivers better fuel efficiency because of its higher octane number
is available in all gas stations

By all means, no benefit will come to individuals who leave ethanol gas in the fuel tank for any period of time. In fact, ethanol promotes fuel deterioration during storage because it is hygroscopic.

Not only does ethanol absorb moisture from the air, causing water contamination that corrodes the carburetor, but it is also a solvent. So, it can damage the rubber and plastic components as well.

Then again, the adverse effects of using ethanol-based fuels can be minimal when using E10 or E5. In any case, rubber components exposed to residual ethanol-based gas will show worse conditions when compared to those in ethanol-free gas after some weeks or months.

Fuel-injected systems designed for ethanol fuels do not experience corrosion because modern engines are made of metals, seals, and rubber that are not affected by ethanol. And this is why you should check your manual before putting E5 or E10 in your lawn mower.

The Simplest Option

If you are still wondering whether you should use ethanol-free gas in your lawn mower, here is a simplified answer: yes, go for it if you have purchased your lawn mower in the last two or three decades.

If you bought new equipment in these recent years, check the manual. Alternatively, contact the reseller or send an email to the manufacturer. They will need to know what model you have, but they will clear any doubt you might still have.

The only reason why you should check before you try is safety. Gasoline is highly flammable and dangerous, no matter what type. But if you put the wrong fuel in your lawn mower tank, you may be exposed to mortal dangers, including explosions.

Generally speaking, ethanol-free gas is the purest form of gasoline. So, it is the best option for small engines. But safety and efficiency are two different concepts and may not go hand in hand.

Old gas goes bad and does not burn. But if you do not remember to empty your gas tank and put ethanol-based gas in it, the lawn mower will not start when you get it back after wintertime. But if you can fill your lawn mower with E5 or E10, on the other hand, your wallet will thank you.