Window doesn't go up. Stuck.
 

My driver's window only go up 1/4 of the way. Then it gets stuck and make very loud sounds like a gun machine.

Where should I start to take care of this problem ? Thanks.

I can't believe the winder is that strong. The ratacha sound is loud and startles me everytime I forget and push the up button. Anyway, it goes down very smooth, but it goes up only 1/4 of the way.

Thanks for your help.

1992 W140 300SD Diesel Turbo, 3.5L .

More than likely your regulator has either broken a rivet or is just plain worn out. Regulators are easy to come by used or buy new. The replacement takes an hour or so but is pretty easy to do. Diesel Giant has a pictoral on door skin removal and replacement that is also helpful. Best of luck!

not sure if the 140 is same as 123, but
 

My 82 SD did the same thing, and the problem was a screw came loose that allowed the glass to slide out of the channel. I loosened all the others, set the glass back in it's slide, tightened up all the screws and all was well. the 126 may be built better than the 140 if it's regulator is pop riveted in. sorry. if it uses screws, you may want to dab on some loctite blue before reassembly.
good luck,
John

Aside from the gear itself I had a problem with the driver's window on my 1981 W123. It worked vyer slowly and seemed to bind. The problem turned out to be bolts that mount the assebmly to the door were very loose. This could have caused strain and wear on the gears. Just something to keep in mind.

My 126 did this also, and the widow had come out of the guide. Got it back in, and it is working again. The regulator in my door was metal and looked like it was strong eneough to lift the car.

I opened up my door twice, and couldn't figure out how anything worked under there. It made me feel stupid. So I applied what I did know. I pulled the window up, measured, and then put a 2X4 cut perfectly that holds the window up the whole way. Now my passengers can't have their windows down, I guess it just sucks for them. A new regulator, which I suspect I may need, is $280 for my coupe, and I'm not that motivated to get one when a free 2X4 did the job.

Anything I should watch for during the opening process ? Thanks. Where should I start ? Where to pull things apart etc. :-)

Answer:
 

Inner Door Panel Removal DIY Links
http://www.peachparts.com/shopforum/diy-links-parts-category/150747-inner-door-panel-removal-diy-links.html

PART NUMBER SEARCH RESULTS WITH PRICES
Vehicle 1992 Mercedes Benz 300SD
Part: Window Regulator Rivet
O3043-61962 Window Regulator Rivet IN STOCK $0.49

http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1WW02D0M91X412F0IE&year=1992&make=MB&model=300-SD-003&category=All&part=Window+Regulator+Rivet



Vehicle: 1992 Mercedes Benz 300SD
Part: Window Regulator
Select one of the products from below
---------------------------------------
Window Regulator
Front - Left
without motor
Prior to listed chassis cut-off requires (4) 003 990 24 97 rivet. Chassis: A 331384-
------------------------------------------
Window Regulator
Front - Right
without motor
Prior to listed chassis cut-off requires (4) 003 990 24 97 rivet. Chassis: A 331384-
---------------------------------------

Window Regulator
Rear - Left
without motor
Requires (5) 003 990 24 97 rivet for installation.
---------------------------------------

Window Regulator
Rear - Right
without motor
Requires (5) 003 990 24 97 rivet for installation.

http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1WW02D0M91X412F0IE&year=1992&make=MB&model=300-SD-003&category=All&part=Window+Regulator


http://www.detali.ru/cat/oem_mb2.asp?TP=1&F=140134&M=603%2E971&GA=722%2E367&CT=F&cat=19B&SID=72&SGR=045&SGN=03

I had a brand new regulator put in over the summer, and it worked for a short while and now gets stuck again. I suspect the window may be out of the guide like yours was, rather than it being the regulator. How can you tell if it's out, and is it easy to get back in?

it happened to me
 

when my window started making the machine gun noise, it was because the gears along the regulator arm got worn (but more like mashed-up)