If its an 8N with a M-S TSX carb, the needle should be out about 1-1/2 turns and it takes airflow through the venture to depress the pressure at the main nozzle and suck the fuel out of the fuel bowl. The low speed and idle systems have ports above the throttle plate that supply idle fuel and transition fuel respectively. The supply passages to these ports must be open. These carbs need to be cleaned very well and all passages must be clear. the float level must be set correctly. They are a good, simple, pressure balanced carb and they respond well to cleaning and new gaskets, needles etc. For the 8N application I believe the initial settings are ide air 3/4 turns open and main jet 1-1/2 turn open.