F motor, Trollhole Carb. Was leaving kids soccer game and wants to stall on idle. Runs great when going down the road. Idle it wants to stall out, some black smoke out the pipe when at idle. Looked at carb when I got home. No gas in the bowl. Some gas coming out the shaft in the pictures. Just wet to the touch. Wipe it and it gets wet again. Pictures show in green were it is seeping. Any Ideas?