Re: 1947 sea king 3 hp
Top needle is low speed, bottom is high speed. The little tube is a drain for unburned fuel/oil from the crankcase...it will dribble, no worries. Baseline settings for carb: top/low speed needle 1 and 1/2 turns out from lightly seated, bottom/high speed needle about 3/4 of a turn out from gently seated. Gently seated means turn them clockwise until they stop...no tighter...then back them out to spec setting...you'll need to adjust both with the motor on a boat and running to get the carb settings really dialed in. Get it up to speed, then adjust the high speed needle to where the engine runs best then tighten the lock nut...same with the low speed only the engine is idling after making the high speed adjustment. Good luck, those are nice little motors.