Fuel comes in many types, including regular and premium. Using the right gas in your lawn mower improves fuel efficiency, boosts performance, and increases the engine’s life. So, what type of fuel does a lawn mower use?
Lawn mower engine needs fresh unleaded gasoline with an octane rating of 87 or higher and an ethanol content of 10% or less. In 2-stroke engines, 2-cycle engine oil must be mixed with gasoline for the necessary lubrication.
Using a wrong type of fuel can damage your lawn mower engine or impair how it performs. If your lawn mower won’t start, idles roughly, stalls out, or makes a “knocking” sound, then check if you have the right type of fuel.
What Type of Gas for Lawn Mower?
According to Briggs and Stratton, good gasoline for your lawn mower must meet the following requirements:
- The gas must be clean and fresh. It takes about 30 days for fuel to start deteriorating, especially if it has not been stabilized.
- The gas should have a minimum of 87 octane/87 AKI (91 RON) if you are operating at a high altitude above 5,000 feet (1524 meters).
- Gas with up to 10% ethanol is acceptable for small engines or up to 15% MTBE (methyl tertiary butyl ether) for four-stroke engines.
- Canned fuel products that combine ethanol-free unleaded gasoline with a fuel stabilizer are also accepted for lawnmowers.
- The fuel must meet the RVP rating of the region. This is a measure of fuel volatility in various temperatures. Gasoline refineries lower fuel RVP in summer and raise it in winter.
Regular or Premium Gas for Lawn Mower?
You’ve heard about regular and premium gas, especially in automobiles. To this point, everyone knows that premium gasoline performs better than regular gasoline. But the truth is that premium gas only works effectively in specific engine models.
Octane rating is what makes regular gas different from premium gas. Regular gas has an octane rating of 87, while premium gas has an octane rating of 91 to 93. Fuel with a higher octane rating can stand up to higher compression before it detonates, thus reducing cases of knocking” or “pinging” in the engine.
Engines with high compression ratings or turbochargers often require high-octane fuel 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 gasoline type, the fuel must be stabilized when winterizing a lawn mower or storing it for longer. Unused fuel takes about 30 days to deteriorate. Bad fuel attracts moisture in the engine and clogs the fuel lines.
Adding a stabilizer to the fuel keeps it fresh for at least 24 months. There is usually a recommended ratio of mixing fresh gas with stabilizer; 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.
It is not right to store a lawn mower with an empty fuel tank, as some sources suggest. In freezing temperatures, the humid air in the tank will condense to form water droplets. This will cause corrosion in the tank and the fuel lines.
Where to Get Gas for Lawn Mower
You can get lawn mower gas at various gas stations. Some stores also sell stabilized canned fuel. Remember to mix your fuel with a 2-cycle oil if operating a two-stroke engine. Four strokes engine lawn mowers have separate compartments for oil and fuel.
Gasoline prices 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, 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
Learning how to put gas in a lawn mower directly from the jerrycan is important. Some people have accidentally put gas in the oil tank and vice versa. Here is how to do it the right way.
- Move your lawn mower to flat ground, turn off the engine and disconnect the spark plug wire.
- Locate the gas tank on your lawn mower. The small tank can either be on the side or under the seat.
- 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.
- Remove the gas cap by twisting it in a clockwise direction. Some lawn models provide a key for locking and opening the gas cap.
- Place a funnel in the gas receptacle if your gas canister doesn’t have a pouring nozzle.
- Gently pour the gas from the can directly into the gas receptacle until the tank gets full.
- Replace the gas cap, and screw it on tightly.
- Use a rug to wipe fuel spilled on the tank or other mower parts.
- Reconnect the spark plug wire and start your lawn mower engine.
Regular gas with an octane rating of 87 or higher and an ethanol content of 10% or less is the right type for a lawn mower engine. A premium gas may not add any importance when used in a lawn mower. Always add fresh, stabilized fuel when storing your lawn mower for more than 30 days.