Originally Posted by
DesertRat
The upper hinge pin isn't supposed to be rotating in the caster block, it's held solid in the caster block and the arm twists on the pin. If it's sticking, ream out the arm.
If your doing anything to the caster block, its sanding the ends of it so the spacers dont cause a bind. The pin itself needs to be pinched. Like the above mentioned, ream the upper A.