1. Before beginning any adjustments, check to make sure that the throttle and choke control cables are in good working order, and that they are correctly connected to the throttle and choke linkages on the carburetor.
2. With the engine off, turn the adjusting screw until the throttle plate is just slightly open.
3. Start the engine and let it warm up.
4. Check the engine idle speed (RPMs).
5. If the idle speed is too fast or too low, adjust the idle mixture screw located on the primary venturi of the carburetor. Make small adjustments as needed until the engine is running at the correct idle speed.
6. With the engine running, observe the choke plate. If the choke plate is slightly open, adjust the choke rod link to close it.
7. Adjust the main jet in the carburetor to set the fuel mixture.
8. Check the high speed air screw to make sure it is properly adjusted.
9. Check the engine again for any performance issues. Adjust the carburetor as needed until the engine is running smoothly.