Window problem?
 

I have a 1983 300SD TurboDiesel, 126.120 Chassis, and my driver window won't go all the way up. When I push and hold the button the window begins to go up normally and as soon as it gets to about and inch from shutting, it stops and a clucking sound begins. Any suggestions on how I can fix it?

Looks like you might have to replace the glass. It sounds like the bracket that the glass is attached to has rusted and flared out. Therefore, causing the noise as the window goes up and hits against the internals of the door. Take the door panel off and observe as you operate the window.

There is a possibility that the lifter has missing teeth which prevent it from going futher. It happened to my 380sel before. I took it off and filled that section with a welding machine and then hand filed to reconstruct the missing tooth. It'll take a little bit of time.

my driver's window has a similar problem. I have all the teeth on motor and arm. If I apply some hand pressure to the arm it goes up smoothly but drops when I let go. I figuired the arm/gear housing must be distorted. I hammered it a bit ( removed it of course) and got another 3 inches of good travel. It works fine on the bench but installed with window is the true test. I will attemt round two this weekend.

My 300D passenger side window stopped this week. It will not go down. Will be taking it apart over the next couple weeks or so to try to see what is going on.

Couldn't wait till the weekend after this thread. Took the thing out and re-formed it. The long arm gear was slipping uder load from the pinion gear on the motor, thus the click click click. The frame of the mechanism had become distorted after 25 years. I put it in the vise and gently reformed it so the gears had a positive mesh. It is a bit sluggish but can't but a new one right now. my window finally rolls all the way up. The arm (rack) gear should ride in the center or the pinion. Mine was slipping to the outside. Be careful as the frame is made of pot metal and can break under too much stress.

Window problems
 

Good that you found the problem. For what its worth, I have had a few electric window problems with my 85 300D which may be useful for others:

Bumping window reaches upper stop...due to worn down teeth on regulator...original cause was that the mounting bolts that hold regulator to door frame came loose, one came out, allowing play...the skipping gear on the motor wore down the teeth. Good idea to check all these bolts, apply locktite and tighten.

Sometimes window goes down but not up, or rear window can only be operated from door switch and not from console. After opening and closing door, window works fine (or some variation of this scenario). Usually rear doors. I have found, both on my car and friends cars, that the problem is that the insulation on the wires going from the body into the door (inside the black rubber flex boot) crack and short due to repeated flexing when opening and closing door. To fix, you need to remove door panel, detach wires to give more play, pull out rubber boot and slid up wire harness exposing the problem area and repair. Electricians tape will fix, but will not preclude another crack in old wires. Best to cut and splice/solder new wire. Things are tight in there...no room for butt connectors...best to solder and use heat shrink tubing.

The most common problem ( as i am sure you all know) is the need to regularly clean out the switches on the console, remove carbon/oxide from contacts, etc. Luckily Mercedes designed these things to come apart and re-assemble easily!! When you do this, make sure you lubricate the ball bearings with heavy grease, otherwise the bearings rust making operation of the switch rough, sometime switch will stick in on position...easily fixed by putting in new bearings from junkyard.

window problem
 

I was interested to note the remarks on clicking noises when raising power windows. My driver's window on '82 300SD goes all the way up, but if you hold the button a second too long, it makes a very loud rapping noise -- like someone beating on your door with a hammer! Very alarming! I plan to tear it down soon to see what's going on. I recently had to do the passenger door, as the glass jumped the front channel. It was a pain getting it all together again, by the way. Just a tip -- one of the actuator arm connections to the glass in with a small bolt, the other is a slider. The bolted one allows a forward/back adjustment of the glass, so as to keep it tight in the front channel. Make sure this is properly adjusted, or your glass may jump the channel.