There is a rubber friction disk in the motor drive. As the disk ages it becomes less effective.
I modified mine by removing the rubber several years ago. Memory tells me I fabricated a disk from some large washers and bolted them in such a way it became a frictionless system.
So far no fingers got in the way when closing the window and nothing else failed because the friction disk was reconfigured.
Friday, July 31st, 2009 AT 10:08 PM