stuttering rear window
 

Well hello!

My passenger rear window on my 1984 300D goes "buh-buh-buh-buh-buh" when i "roll" it up (its electric). Going down is not as smooth as it should be, but going up definitely vibrates, bounces, and at the top the motor will continue to run.

Anyone out there had a similar problem, that could offer some insight betfore I take my door apart? Thanks for your time,

Jeff

My rear pax side door window makes the same noise...My Indy claims its the motor going out..We'll see, too hot to roll it down now anyhoo...


Dakota

1981 300D W123 "China Blue" 193K

My drivers side front window did the same thing. It's my new to me 1978 300D. Well, about the third or fourth time I heard a pop/clank and now the window moves up and down by hand only. I hear the motor but no effect on the window. Search suggests the regulator has died. I'm hoping the track has separated from the window and i can just glue it back. Looking forward to more experienced opinions on this.


Kevin
1979 240D manual
1978 300D manual

i like the glue and track idea. i guess i should start pricing regulators just in case, though. thanks for the ideas.

My pass rear did the same until about 6 months ago, now it doesn't do anything....I'll get to it one of these days...

My left rear does this. I haven't taken it apart yet to see what is going on, as I need to do some more important maintenance stuff. I have been avoiding using it if I can. I will be watching this thread to see what is going on. The frequency of the bub-bub-bub seems like it would be a gear in the motor.

Your indy is way off, its the regulator that needs replacing. Usually the motor is OK but its the shape of the frame that constitutes the "regulator" that causes the odd noises and irregular motion.
The 123 regulators are made of pot metal that warps when the windows are topped up and the button held a little while to be certain the windows are all sealed up nice and tight. Place your leg against the door panel on a good working 123 and feel the panel push out when the window is raised up. Things get pushed out due to the force of the frame carrying the glass and its friction in the window channels.

OTOH if one lowers the window glass after is is topped out and leaves a small air gap at the top the regulators might last a hundred years.

The gub gub noises are when the motors' gears have eaten out the teeth on the arc shaped part of the regulator. Very common in older 123's

Dieseldiehard is correct in what he says about the regulator warping when the window is in the closed position. the motor tweeks the regulator, you can see it when the door panel is off and the window is run up and down.
I tap the switch after the window is up to take the pressure off it.

My drivers window quit a few years ago. it was the regulator that broke. there are two rivits that hold the center part together, and they snapped off. probably could replace with a couple bolts and then tack weld.

I think the new reg was $135.00 from my indie. could get one from the junk yard, but then most of that stuff is 22 yrs old and older.

Just click on parts and get from Fastlane.

Charlie

No doubt about it, the two above are correct. Usually the pot-metal regulator is cracked or warped. I reformed one, but have had two others cracked and useless. Motors and their gears seldom fail. When the regulators deform, the teeth of the motor gear and the regulator teeth don't line up, ie: gears don't mesh correctly, and pop pop pop pop.......