Is there a small gib screw in your clutch knob.? If this is like most machines it is designed to turn between three lobes of an odd washer between the clutch wheel and the and wheel. if that screw is missing you won't get it to work.
Have you tried holding the handwheel with a gripper as you tighten the clutch wheel?
If these don't work you may have to that the gib screw loose and tighter the clutch wheel less than 1/3 of a turn and tighten it again. Those are the first 3 steps to try. IMHO
Inside of the clutch wheel and the clutch washer will be shown in the next post.