John Deere S120 Operator's Manual
![John Deere S120 Tractor manual cover](/images/WOMLVBNfwnHBvGJFBWZrCeib/thumbs/thumb175x175.webp)
Basic maintenance includes checking the engine oil level, cleaning or replacing the air filter, inspecting the spark plug, and checking the tire pressure. Ensure that you also lubricate the pivot points and inspect the belts for wear.
If the tractor won't start, check the battery connections to ensure they are clean and tight. Verify that the fuel is fresh and that the fuel valve is open. Inspect the spark plug for fouling and replace it if necessary.
Uneven cutting can be caused by a dull or damaged blade, improper deck leveling, or tire pressure discrepancies. Sharpen or replace blades, adjust the deck height, and ensure all tires are equally inflated.
Before use, check the oil level, fuel level, tire pressure, and ensure that all safety devices are functioning properly. Inspect the belts and blades for wear and check the battery charge.
To clean the mower deck, first ensure the tractor is turned off and the blades have stopped. Use a brush or a low-pressure hose to remove grass clippings and debris. Avoid using high-pressure water as it can damage components.
For winter storage, clean the tractor thoroughly, check and change the oil, add fuel stabilizer, remove the battery and store it in a warm place, and cover the tractor to protect it from dust and moisture.
To improve fuel efficiency, ensure the air filter is clean, the spark plug is in good condition, and the tires are properly inflated. Regularly service the engine and keep the mower blades sharp.
If the belts are slipping, check for proper belt tension and adjust if necessary. Inspect the belts for wear or damage and replace them if needed. Ensure that the pulleys and spindles are clean and free of debris.
To level the deck, park the tractor on a flat surface. Measure the distance from the deck to the ground on both sides and adjust the deck hangers until the deck is level. Recheck measurements to ensure accuracy.
Remove the blades from the mower, use a grinder or file to sharpen the cutting edges, ensuring an even angle. Balance the blades before reinstalling to prevent vibration and uneven wear.