I just picked up a 1980 Mercedes 300SD and noe of the windows work properly. When I move the switch to roll the window down, it makes a grinding sound but not much happens unless I move the window by hand at the same time someone activates the switch.

Will a window regulator kit and cleaning correct this? It seems like the motor is working. Appreciate any advice including how to remove the unit.

Thanks,
Fred

 

Sounds like the window trach gears might be shot. You will have to pull the door panel. Probably an new regulator, Or you might get really lucky and some lithium grease might loosen things up. None of the windows work? Where was the car kept? outside? Did they work when you bought the car? Try taking off the door panels, clean all the parts that "move" the window, use a degreaser if you have to and they try the lithium grease, spray can with one of does little red nozzles, If there no protectors, that is plastic water resistant paper cover the inside of the door after you get the panel, get some, A thicker piece of plastic will usually do. If the cleaning and grease works make sure you use the protective covers and secure it with masking tape and remount the panel.

If not you probably need new regulators maybe tracks, etc. Good Luck