Replaced upper and lower thimble's, lever arm, cam closure. Door stop was not the problem, but ordered it and replaced it too. The door of course has to come off, remove the top hinge, and lift it away. Lubricated moving parts with silicone spray. Be sure and put the door back in the open position, so the lever arm and cam closure can properly interact, then close the door. Remove the plastic grate at the bottom to get at the lever arm. Presto. Problem gone. Don't put excessive weight back in the door, this is what causes the problem.