The maintenance of a lawn mower is essential to its performance and life span. Changing the oil on a regular basis can help the machine last for years. Changing the oil of a lawn mower is very similar to the same process for a car or truck. The major differences are the type of oil used and the location of major parts.
Locate the engine. In most Toro riding mowers, the engine is located behind or partially under the seat.
Locate the oil fill spout, oil filter and drain plug. Most Toro mowers will have a simple drain valve instead of a drain plug. However, some will have a drain plug.
Place the drain pan under the drain plug or valve. Make sure the pan is situated to limit the amount of oil spilled during the draining process.
Open the drain valve or remove the drain plug. Some drain valves will require a hose attachment to facilitate draining of the oil.
Remove the filler cap. This will help the oil drain from the engine. When the oil is finished draining, replace the drain plug or close the valve. In riding mowers the oil will drain on its own; however, with push mowers, the mower will have to be tilted to help the oil drain.
Remove the oil filter, if equipped. Wipe the mounting plate and install the new filter. The oil filter should be hand-tight. Turn the filter counterclockwise to loosen, then install the new filter by turning clockwise until hand-tight. You should replace the oil filter after every 200 hours of operation or during every other oil change.
Use a funnel to fill the oil to the proper level with SAE 30 weight oil. Make sure to check the oil level to ensure it is not overfull. The amount of oil can vary by model. Most push mowers will take less than 1 quart, while some riding mowers can take up to 3 quarts. Check the owner's manual or check the dipstick while filling.