Rockman, It sounds as if your engin is 4 cycling at lower rpms because of the rich setting on the LSN . I would try very small leaner adjustments on your LSN ,waiting about 20 to 30 seconds between adjustments till the engine starts to 2 cycle. If it stalls you may have to up your idle a little. Be patient and heat up the engine with a hair dryer before cranking her over.