Carburetor adjustment, help!

Prior to adjusting, the engine ran rough but if the choke was left partially on it ran fairly smooth. After adjusting the two fuel mixture screws the engine ran rougher and drank fuel faster than the tank could supply. The in-line fuel filter (paper element) would fill with air as the fuel was consumed.

What is the proper way to adjust this carburetor, and does the fuel supply line need to be purged of all air (the inline paper element filter always has air in the top)?

Thanks for any help you have to offer.

Paul

I got rid of the inline filter and verified a ample supply of fuel is delivered to the carb.
Verified each plug wire delivers an intense consistent spark which jumps a 1/4 inch gap, checked timing (by the straight edge method), adjusted points (were at .011" now at .015"), plugs are new and gapped correctly, new distributor cap and rotor installed. Disassembled carburetor and found interior very clean, blew out all ports and jets not finding any clogs (carb is less than two weeks old). Checked for intake leaks in the carb and manifold didn't find any.

Idle adjustment screw is backed out 3.5 turns and the main jet screw is backed out 2.5 turns. With these settings the engine runs rough at both low and high speed with lots of misses and pops. Lowest engine rpm attainable with no choke before stalling is probably around 700 - 900 (by ear). Engine actually runs better by backing the main jet screw all the way out to no thread engagement.

By applying approximately 1/3 of full choke it runs much smoother (satisfactory) and a much lower engine rpm is attainable maybe 500-600. I am assuming it runs rough due to a lean fuel mixture (based on the improvement from applying the choke).

Is it possible that the carburetor needs to have a different main jet installed. Is there anything else I can do to correct this, seems like it should run good.

Thanks for your help.

Paul