That small piston looking thing you can see through the top of the carbs is stuck on 1 of my cylinders. It opens by itself but then won't close. It doesn't have anything physically blocking it and I've swapped around the springs and rubber to see if it made a difference but nope. I'm guessing all this does is stuff up the air mix in that cylinder since it's always open. Anyone encountered this problem and can gimme some advice? None of the parts seem damaged or worn either.