* A spark plug wrench
* A flat-blade screwdriver
* A feeler gauge
* A 9/16-inch wrench
1. Turn off the engine and allow it to cool down.
2. Remove the spark plugs.
3. Remove the valve cover.
4. Locate the intake and exhaust valves on each cylinder head. The intake valve is located on the side of the cylinder head closest to the carburetor or throttle body, while the exhaust valve is located on the opposite side.
5. Insert the feeler gauge between the valve stem and the rocker arm. The feeler gauge should be able to fit snugly between the two surfaces, but there should not be any drag.
6. If the valve clearance is not correct, use the 9/16-inch wrench to turn the adjusting nut until the feeler gauge fits correctly.
7. Repeat steps 5 and 6 for the exhaust valve.
8. Repeat steps 3-7 for the other cylinder head.
9. Replace the valve cover and spark plugs.
10. Start the engine and check for any unusual noises. If you hear any unusual noises, readjust the valve clearance.