450 SLC Power window question
 

Need help please
Passenger front window goes down fine, but stops intermittently when trying to raise window back up, and then makes a clunking noise. If I grasp the window glass and gently pull up, it will then come up all the way with the motor. I have the door liner off and I can see that when it makes the noise, the large metal gear on the motor that contacts the window regulator lifting mechanism is not moving so I am wondering if it could be an internal noise (vs. external) in the electric motor itself, perhaps requiring motor replacement.
Any help or suggestions greatly appreciated as I am trying to repair this myself without involving the dealer.
Thank you,
Kurt

Hi Kurt - I'm attaching two helpful links from our site's DIY tech articles on the R107 platform. It sounds like it's the motor that needs replacing. Please let us know if you have any questions.

Mercedes-Benz R107 Window Motor Replacement | 1972-1986 - 450SL, 380SL, 500SL, 560SL | Pelican Parts DIY Maintenance Article

Mercedes-Benz R107 Window Lifting Mechanism Replacement | 1972-1986 - 450SL, 380SL, 500SL, 560SL | Pelican Parts DIY Maintenance Article

Thank you for the links to the technical articles.
I tried to remove the motor and after several hours and drilling additional holes in my inner door skin I was able to get it out. The motor works fine on the bench but once I reinstalled it the window would stop at 3 or 4 places on the way up and only work with assistance from lifting the glass by hand. Also, my motor did not have a clip for detaching the wires from the motor which further complicated the removal. At this point, it is still a work-in-progress to be continued.
Kurt

Removed the power window motor again today, and disassembled the rear cover; problem was the round plastic gear inside had 4 stripped/missing teeth. Ordered new motor and awaiting arrival. Thanks to all for the helpful comments.
Next project will be to remove and replace rear bumper ( $$$ ouch) Kurt

Hi Kurt - glad that everything worked out for you. Please let us know if you need any further assistance or with any part needs.