How to Change Oil on a Rear-Propelled Lawnmower

Wipe the area around the dipstick/oil filler tube then clean the area around the drainage hole located in the bottom of the mower deck with a rag. This prevents debris from getting into the engine while you change the oil. If your mower's engine has an oil filter, clean the filter housing and the area around the filter.

Remove the drainage bolt with a socket and drain the oil into a drain pan. Once all of the oil stops running out of the motor, reinstall the drain plug.

Unscrew the oil filter with a filter wrench and discard the old filter. Fill the new oil filter with 10W30 engine oil then install it. Hand-tighten the filter as much as you can; do not tighten the filter with a wrench. The majority of push mowers do not use an oil filter. If this is the case for your mower, forgo this step.

Remove the dipstick/filler cap and add 1/4-quart of 10W30 engine oil into the dipstick/oil filler tube. Reinstall the cap, then remove it and check the level of oil. Add more oil, as needed, until the level of oil is between the "Add" and "Full" marks. Replace the cap.