04-28-2013, 07:00 PM
It looks like you might be missing the spring steel insert which fits in the slots across the hole in the knob. This is a thin leaf spring which puts pressure on the flat of the shaft and prevents the knob from turning on the shaft.
It might have come loose when you removed the knob. If its lost, you probably can fabricate a workable replacement from thin sheet metal.
It might have come loose when you removed the knob. If its lost, you probably can fabricate a workable replacement from thin sheet metal.