Odd window raising problem '81 300SD
 

Front driver's window. Yesterday it went up with the power button; however, it went up tilting forward or down at the leading edge - not straight. I grabbed the glass, held it level and the power button lifted it fine.

So it obviously is not the sliding jaw. Sounds more like the sliding jaw is no longer sliding - so it pushes up the back of the window instead of sliding as the window goes up.

Anyone experienced this problem? Seems to go down fine but I hesitate to check.

Thx.

The regulator is broken, the sliding jaw is broken off, or the rear "guide" sliding jaw is broken off. The front windows have a "scissors" style regulator, so the window can still move if the sliding jaw breaks.

I'd be putting money on one of the plastic sliding jaws. What a crap design.

In short you won't know till you remover the Door Panel and look in side to discover what is wrong.

Much appreciate the help.

That's why I called this an odd problem. Well acquainted with broken sliding jaws over my 30+ year ownership of the SD (have replaced several over the years) - and it does not act that way. Generally with a broken sliding jaw the regulator will not push up the window. Down - yes - but not up.

You might be right but I do not remember the front regulator having an X scissors design.

If you read my description again, you will see that:
regulator is still working because it still has power and lifts up the window;
regulator arm itself must not be broken because it still raises the window;
sliding jaw does not appear to be broken because it still raises and lowers the window - so it is still whole and attached. Just raises at an odd angle as if the sliding jaw is stuck in one place and will not move side to side.

(Of course all this is just a guess at this point.)

So it seems to me that 1) something dropped onto the horizontal bottom metal rail which keeps the sliding jaw from sliding or
2) the sliding jaw needs grease because it stopped sliding.

I know I will have to take it out; just pondering if this is a new (not sliding jaw )problem. Like Sherlock who solves by pondering the facts. Wondered if it had happened to anyone else.

If it's a grease problem then one of the plastic parts is broken and will need to be replaced.

I'd guess it's the big plastic piece that rides in the rear vertical track. Just a guess but I've only changed one and was a bear because I had no idea how to get it in both the vertical and horizontal tracks at the same time.

I think I took the entire window to it's lowest point after removing the motor and finally finessed it into place.

Yep, there is only one plastic part in the '81 300SD regulator which is the sliding jaw. I have replaced them several times and on all the doors over some 30 something years. Have never had a problem with a regulator, motor, etc - except I had to bend one arm back straight once.

Have some things on my plate now but will at some point take it all apart and will report back.

The W126 has 2 plastic pieces in the front. There's a shaped jaw that slides up and down the window channel to keep the window from rattling and the usual rectangular piece that we all know and hate. The regulator on the front windows is a very different design to the rears, if the bolt that holds the bottom part of the "X" in place has rattled out, or if the plastic slider has broken, the window can operate at an angle or come out of its track entirely (and break).

That is exactly what is happening. It is going up but at an angle. I just do not remember the regulator much. But I do remember how to get the door card off without breaking the plastic retainers.

The sliding jaw in my back drivers window has been broken for several months now so I may just fix both at the same time.

Diseasel300 - just looked at Pelican's regulator for front and it does indeed look different from the back one. Did not remember that. Here is pic of slider in Pelican that is quite strange. Is this the other slider you mentioned?

That is the anti-rattle slider. It is in the front windows only. They also have the square POS that breaks all the time, same as the rears. The fronts also have one "arm" of the regulator firmly bolted to the window rail at the bottom, check that the bolt didn't rattle out!

Great. Thx.

I also remember a channel either toward the front or rear of the door that can be adjusted and may affect how straight the window goes up of down if it is out of adjustment. I've taken to removing the regulator cleaning and greasing periodically when there is a reason.

Will look.

As soon a window becomes slow to open..
 

I remove, clean and inspect the regulator. Any component which isn't in perfect shape gets replaced.

Agree