dont use choke ! 3/4 pumps of acc pedal then should start check see if accelerator pumps on carb are working take carb intake off with pump of pedal is there two cleans sprays of fuel? i dont try to drive mine until engine temp at least 160 f is the fuel pump working correctly ?have u put volt meter on batts when fsc running at 800 rpm ? when starting mine down to minus 1 centigrade i use no choke.