As the weather gets warmer, idle mixture seems too rich. The throttle shafts seem snug. I know that air leak here can cause the carb pistons to rise and richen the mixture. If the pistons are sticking I guess that can cause a rich idle, but shouldn`t that cause other problems? I changed air filters. I can`t find the piston lifting pin on these HS6 carbs. Should the pistons be easy to move up and down by hand? How often have you seen the pistons stick?

I`ve been trying to leave the carbs alone, but I may have to tackle them! The car runs well, but the tailpipe always looks black. I`m beginning to wonder if the ignition coil could be weak. May look at that. Forgive my rambling "stream of consciousness."