What is the solution for an overly rich air-fuel mixture?

[DelCarlos]

When the air-fuel mixture is too rich, first check the choke valve opening and adjust the fuel needle. If there is no significant improvement, remove the air filter screen to see if the engine performance improves. If the above methods are ineffective, finally disassemble the carburetor to inspect the fuel level in the float chamber and the jets. The specific methods are as follows: 1. The first method to address an overly rich mixture is to inspect the fuel line from the fuel tank to the carburetor fitting. If there are issues like fuel leaks or blockages, clear or replace the line; 2. The second method is to check the fuel pump. If the fuel pump is faulty, replace it; 3. Inspect the carburetor's fuel inlet needle valve opening or float height. If there are any abnormalities, adjust them; 4. If the main jet or main fuel passage in the carburetor is clogged, clean and clear it; 5. If the gasket is damaged or leaking, replace it.