It's all guesswork without a CO meter, but the standard way to do it without, is to turn the screw in the lean direction until the engine begins to stall. Then turn it out slowly until it just runs nicely. You've now found the leanest mixture where it runs properly.
11-09-2013 10:15 PM
Re: Carburetor Adjustment
Find the idle mixture screw on the carburetor, turn it in for richer, turn in out for leaner. The screw controls the amount of air, not the fuel.
11-09-2013 05:19 PM
Would someone talk me through adjusting the carburetor on my Atomic Four?
At low rpm I'm making smoke, which goes away when powered up, so I'm thinking I need to "lean out" the carb.