What Kind of Gas Does a Lawn Mower Use?

A gas powered lawn mower engine will need fuel to run and produce power required for the cutting of grass. Fuel comes in many types including regular and premium. Using the right gas in your lawn mower improves fuel efficiency, boost performance and increase the life of the engine. So what type of fuel does a lawn mower use?

You’ll need to go through your user manual to understand the type of fuel for your lawn mower. Usually, unleaded gasoline with octane rating of 87 or higher is suitable for a lawn mower. For two stroke engines, an addition of two-cycle engine oil into the fuel will be required.

A wrong type of fuel can damage your lawn mower engine or impair how your mower performs. If your lawn mower won’t start, idles roughly, stalls out, or makes a “knocking” sound, then you have case of incorrect or stale fuel. You’ll need to drain the gas from your lawn mower, clean the carburetor and refill with the right type of gas.

What Type of Gas for Lawn Mower?

To avoid dealing with costly damages in your mower’s engine or unnecessary expenditure on high octane premium fuels, then you need the knowledge on the kind of gas to use in your mower. According to Briggs and Stratton, a good gasoline for your lawn mower must meet the following requirements:

  1. The gas must be clean and fresh. It takes about 30 days for fuel to start deteriorating especially if it has not been stabilized.
  2. The gas should have a minimum of 87 octane/87 AKI (91 RON) if you are operating at high altitude above 5,000 feet (1524 meters).
  3. Gas with up to 10% ethanol is acceptable for small engines or up to 15% MTBE (methyl tertiary butyl ether) for four stroke engines.
  4. Canned fuel products that combine ethanol-free unleaded gasoline with a fuel stabilizer are also accepted for a lawn mower
  5. The fuel must be meeting the RVP rating of the region. This is a measure of fuel volatility in various temperatures. Gasoline refineries lowers fuel RVP in summer and raises it in winter.

Regular or Premium Gas for Lawn Mower?

You’ve heard people talking about regular and premium gas especially in cars. To this point, everyone knows that premium gasoline performs better as compared to regular. While this is not far away from the truth, premium gas only work effectively when used in specific engine models.

Octane rating is what makes regular gas different from premium gas. Regular gas has an octane rating of 87, while for premium it ranges from 91 to 93. Fuel with a higher octane rating can stand up to higher compression before it detonates thus reduced cases of knocking” or “pinging” in the engine.

Engines with high compression ratings or turbochargers often require high octane fuel found in premium gas for optimal performance and fuel efficiency. This is why you don’t need to use premium gas in a lawn mower or any other small engine.

Stabilizing Fuel for Lawn Mower before Storage

Regardless of the type of gasoline you use in your lawn mower, fuel must be stabilized when winterizing a lawn mower or storing it for longer. Unused fuel takes about 30 days to deteriorate. This will result to clogging in the tank and mower’s fuel system which will give you problem starting your lawn mower.

Addition of stabilizer in the fuel makes it to remain fresh for at least 24 months. There is usually a recommended ratio of mixing fresh gas with stabilizer and you can get it on the product label.

Once you have stabilized the fuel, fill it into the tank to 95% capacity leaving a small room for gas expansion in hot conditions.

You will meet some sources recommending that you store your lawn mower without any fuel in the tank. This is a wrong approach of safeguarding your lawn mower’s fuel system during storage. Condensation will always happen when the tank is empty and the moisture droplets will lead to corrosion in the system.

Where to Get Gas for Lawn Mower

You can get lawn mower gas in various gas stations. Some stores also sell stabilized canned fuel. What is important is to know the right fuel type for your lawn mower. Also remember to mix your fuel with a 2-cycle oil if you are operating a two stroke engine. Four strokes engine lawn mowers have a separate tank where oil is added.

Gasoline price vary from one place to the other. The variation in costs depends on the type of fuel available and the volume you are buying.

If you decide to buy your petrol in a canister or jerrycan then you have more work to do. You will have to pour the gasoline into the lawnmower tank yourself.

How to put Gas in a Lawn Mower from a Can

It is important to learn how to put gas in a lawn mower directly from the jerrycan. Some people have accidentally put gas in oil tank and vice versa. Here is how to do it the right way.

  1. Park your lawn mower on a flat ground, turn off the engine and disconnect the spark plug wire.
  2. Locate the gas tank on your lawn mower. The small tank can either be on side, top or housed on your lawn mower.
  3. On the tank, search for the gasoline receptacle. It is usually coved with a black cap and for some models it bears a gas pump symbol.
  4. Remove the gas cap by twisting it in a clockwise direction. In some lawn models, a key is provided for locking and opening the gas cap.
  5. Place a funnel in the gas receptacle if your gas canister doesn’t have a pouring nozzle
  6. Gently pour the gas from the can directly into the gas receptacle until the tank gets full.
  7. Replace the gas cap, and screw it on tightly
  8. Use a rug to wipe out any fuel that has spilled on the tank or other parts of the mower
  9. Reconnect the spark plug wire and start your lawn mower engine.

Final Thought

Always use the right type of gas recommended for your lawnmower engine. Regular gas with octane rating of 87 or higher work best in most small engines. A premium gas may not add any importance when used in a lawn mower. Most importantly, fill a lawn mower gas tank with fresh stabilized fuel when storing it for more than 30 days.

Leave a Comment