I’ve got a IIb or thereabouts. Holding the camera so the lenses are facing me, I move the cocking lever to the left to cock the shutter — I can hear a spring making noise as it is stretched until the shutter cocks, then I can move the lever back to the right, to the bottom of the arc, to where moving it further to the right would release the shutter. I have to move the lever back to the center, there is no spring to pull it back to center. The lever, however, is not swinging loosely after the shutter is cocked; there’s a bit of friction in the mechanism such that the lever must be moved by the hand. It won’t move left or right on its own.