How Does Running at Full Throttle Benefit a Mower?

When you’re running your riding mower, your throttle setting regulates the amount of air that makes its way into the fuel-air mixture, changing the speed at which your engine runs. It doesn’t necessarily control the speed of the mower itself, but merely the speed of the engine. Many of us tend to run our throttle partially opened, but there are certain benefits that can be had by running your mower at full throttle as often as possible:

Cleaner cut of the Grass

As the engine runs at higher rotations, the blades of the mower deck will spin at a higher velocity. This high velocity allows the blades to make a swifter, cleaner cut to the blades of grass, creating a yard that is more uniform.

Less Engine Stress

Your riding mower engine is designed to be run at full throttle, so running it at less than that can create undue stress on the engine and parts. This includes, but is not limited to:

• Poor battery recharge rate and shortened battery life – The faster an engine runs, the faster it recharges the battery that is drained severely on ignition. Additionally, some engines do not even begin to recharge the battery until a certain level of RPMs is reached, which requires high throttle.
• Vibration – The engine and other moving parts are expecting the vibrations caused at full-throttle operation. Operating with less throttle creates different vibrations, and may cause some severe shaking of the engine. Extremely fierce vibrations can cause malfunctions and equipment failure.
• Increased full usage – Contrary to popular belief, low throttle does not save fuel. If you run your mower at half-throttle, you will cause the engine to lug, and it will use more fuel trying to keep up. More fuel means a greater likelihood of “washing” the cylinders, where the fuel washes the lubricating oil off, creating hotspots, shortening the life of cylinders and pistons, and increasing oil use.

Engine runs at a Lower Temperature

Running at full throttle increases the speed of the cooling fan, meaning that more cool air is being pushed over the engine, causing the operating temperature to drop. Even more necessary is the air that is pushed over the transmission. Hydrostatic transmissions produce heat when in use, and they require a fan to cool them down. If this fan runs at a slow speed, the transmission will overheat, leading to loss of power, particularly on hills, and permanent damage to the transmission.

Less Likely to Bog Down in Heavy Grass

With the engine operating at full throttle, the blades will be spinning at full velocity, meaning that they will not get bogged down in heavy patches of grass. Running at partial throttle allows the grass to bind the mower up, and it could lead to having to get under the mower deck and manual clear out the deck.

So after you get you riding mower started and warmed up, crank that throttle up and don’t bring it down until you are planning to stop for the day. Your mower will be better off for it.