I have a question re: the power unit in the door.

Everything seems to be in place, the gears appear to be good, and the unit runs, it just doesnt move anything.

I once had a Ford with the same problem and it turned out to be that inside the final gearbox there were 3 rubber wedges that acted as a clutch should the window be forced. They had fallen apart with age.

Does my Mercedes have something like that, or some other exotic means?

Any help will be appreciated.

Bat

You sure that the teeth on the regulator are good? Sure that its not bend and not making contact with the motor drive gear?

__________________
1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg

Mercedes window motors don't have the three plastic rollers in the motor-gear.
Typically, the alloy regulator frames warp after so many years, allowing the regulator teeth to get out of line with the motor-gear. Sometimes it's possible to partly straighten the frame and/or shim the motor mounts with washers to get the gears to mesh again.
There is a stronger, redesigned replacement window regulator availible for the front doors.

Happy Motoring, Mark

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DrDKW

Thanks to both of you for replying.

I havnt pulled the unit yet, just ran my fingers around the gear which seems to be ok.

Alignment is most likely the problem since there is no clutch in the motor drive gear.

This weekend I'll pull it out and find the culprit.

Bat

I seem to recall that the Mercedes window motor runs on a worm gear. It drives a large plastic gear that sometimes will lose a tooth or will just get worn down.

If your gear teeth are worn away then it is usually easier to just replace the entire unit. Just post a notice that you need one on here or in the parts wanted. I have a few spares and I am sure others do to.

The part number on the unit is not enough to get the right one. You must also have the correct number of teeth on the gear to make it mesh up. There are about three different gear raitos, but all are very common and not hard to find. It is just something to be aware of.

Be prepaired to put some new grease into the gear unit when you take it apart. Over the years the grease will dry out a bit and needs to be renewed. Carefull... A little bit of grease goes a long way here.

Hey guys,
Thanks for your input. I finally got to pull it out today and found the gear bearing mount on the regulator had split in half. It fell out in my hand.
Motor and gear check out ok.
Anyone that has a used one, let me know. Part # is 1237200846

RF door.

Thanks again
Bat

If it's one of the front-door regulators, best find one of the late W123 units. It's a much stronger design than the early version.

Happy Motoring, Mark

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DrDKW

Lubriplate is a great long lasting grease for that gear train too.

__________________
1985 300D 198K sold
1982 300D 202K
1989 300E 125K
1992 940T

"If you dont have time to do it safely, you dont have time to do it"

"The democracy will cease to exist when you take away from those who are willing to work and give to those who would not."

I dont know if any of you have dealt with Socalmercedesparts.com, but I found a used upgraded regulator for $125. I was shocked at the price for the new one's, over $300 w/o the motor.
Eddie Stein @Socal has been a lot of help, they sell new and used parts.

Thanks again for your input.