Poor Fuel Mileage: Carbureted

Verify correct carburetor idle and fuel mixture adjustment.
Verify base timing is correct and that timing advance system is functional.
Ensure air intake system is unrestricted.
Verify choke is fully open after engine is warm.
Ensure fuel level is at specified mark on carburetor sight glass.
Check canister purge control valve operation.
Ensure engine has sufficient compression.
Ensure exhaust system is not plugged.
Check carburetor mixture control duty cycle using dwell meter.