1. Start the engine and let it reach operating temperature.
2. Turn on the headlights and air conditioner to increase the electrical load on the engine.
3. Use a tachometer to measure the engine's idle speed.
4. If the idle speed is too high or too low, use a screwdriver to turn the idle speed adjustment screw on the carburetor.
5. Turning the screw clockwise will increase the idle speed, while turning it counterclockwise will decrease the idle speed.
6. Make small adjustments until the desired idle speed is reached.
7. Once the idle speed is set, turn off the headlights and air conditioner.
8. The engine should now idle smoothly at the desired speed.
