CIL,
Pounding on those shafts can bend them. Try to avoid that.
Since the shaft will move down on it's own slowly there is still some gummed up oil or something in the shaft bore and or on the shaft. You'll really need to use some form of solvent to remove it. I've used denatured alcohol and Hoppe's #9 gun cleaning solvent. A bronze bore cleaning brush down in the shaft's holes will help too.
You might want to carefully take that shaft out again and make sure it's not bent and while it's out thoroughly clean it and the holes it rides in.
Joe