1. Gather the necessary materials and tools.
- New oil (SAE 30 or 10W-30)
- Oil filter (if applicable)
- Oil drain pan
- Funnel
- Wrench
- Rags
2. Prepare the mower.
- Park the mower on a level surface.
- Turn off the engine and allow it to cool down.
- Disconnect the spark plug wire.
- Place the oil drain pan under the engine.
3. Drain the oil.
- Remove the oil drain plug with the wrench.
- Allow the oil to drain completely into the oil drain pan.
4. Replace the oil drain plug.
- Once the oil has drained, replace the oil drain plug. Tighten the plug snugly with the wrench.
5. Add new oil.
- Using the funnel, add new oil to the engine.
- The oil level should be between the "FULL" and "ADD" marks on the dipstick.
6. Replace the oil filter (if applicable).
- If your mower has an oil filter, it should be replaced at the same time as the oil.
- Locate the oil filter and remove it with the wrench.
- Apply a thin coat of new oil to the gasket of the new oil filter.
- Screw the new oil filter onto the engine and tighten it snugly with the wrench.
7. Start the engine and check the oil level.
- Reconnect the spark plug wire.
- Start the engine and let it run for a few minutes.
- Turn off the engine and check the oil level on the dipstick.
- If the oil level is below the "FULL" mark, add more oil.
8. Dispose of the old oil and filter properly.
- Used oil and oil filters should be disposed of according to local regulations.
- Many auto parts stores offer oil recycling services.
