Diesel Lawn Mowers Vs. Gas Lawn Mowers

About Lawn Mower Engines

• Most lawn mowers use a small engine because they’re easily operated and maintained. They also burn less fuel than a larger engine, which means you’re spending less time refueling and more time cutting your grass. Most small engines are two-stroke, rather than four-stroke, which means they require half the number of rotations to spark the fuel and produce the energy needed to power the lawn mower. Small engines also produce less heat and rely on the surrounding air to cool them.

Versatility

• Diesel lawn mowers are designed to run on diesel fuel, but can be made more environmentally friendly by using biodiesel instead. Many diesel lawn mowers can operate with this reusable, often recycled natural fuel that consists of vegetable oil and animal fat. It runs as efficiently as diesel in your lawn mower and also benefits the environment and cuts fuel costs. Gasoline lawn mowers cannot be operated with anything but gasoline. Putting another fuel in such an engine can ruin the mower entirely.

Fuel Consumption

• Diesel fuel and gasoline are refined from crude oil. The difference lies in how each burns. Diesel is ignited using high cylinder pressure. The high compression ratio of diesel fuel creates enough heat inside the engine to ignite the fuel. Gasoline is ignited by a spark to burn and cannot withstand as much pressure as diesel fuel. According to Grasshopper Mower, in terms of fuel economy, this difference in burning means that a 25 horsepower diesel mower will burn about 0.9 gallons per hour, while a gas engine of a similar size burns twice that much. Diesel lawn mowers can cost more than gasoline, but fuel economy is better, so the savings overall tends to be with diesel lawn mowers.

Horsepower

• The numbers you see on your lawn mower that refer to horsepower refer to the engine’s peak ability, or maximum amount of power. Gas mowers must be at full throttle to reach this peak, and if pushed beyond this, the engine may stall out. A diesel mower has a lower horsepower rating, but when running full throttle, it will not stall and quit because a diesel engine does not rely on rpms for power as heavily as a gas mower does.