It helps to remove the intake manifold when doing the Kroil/tapping technique so that you can get to both the inside and the outside of where the shaft enters and exits the exhaust manifold. My hunch is that the jamming happens more from the inside out than the outside in, so approaching from just the outside might not work. The inside can be caked with carbon deposits, so it also helps to take a small chisel or screwdriver to clean the both sides on the inside where the shaft goes through the manifold. Try to get the shaft and the manifold down to bare metal on the inside so that the Kroil can do its thing.
I'll shoot them with Kroil and tap them a few times a day. They can take several days to break free, so be patient. You'll feel some play at first when you tap the shaft as it moves side to side, then you'll finally feel the baffle move a bit when you twist the weight. Once it starts to twist, they tend to break free with one or two more treatments.
You don't have to be too gentle when you tap, but don't be a gorilla either. There is some lateral play the way these things are designed, and you are trying to take advantage of that by tapping to break the jam with side to side movement.
I'll give mine an occasional generous shot of Kroil or Blaster whenever I have a can out to do something else under the hood.
Good luck,
Matt
