I had the driver's side power window regulator replaced in my 81 300D and it's working much slower than the other three windows. Anyone have any ideas?

There are a number of possibilities. Did the replacement regulator include a new motor?

(1) Binding in the window tracks or the regulator. Test for this by removing the motor and operating it alone, unconnected to the window. The difference in motor speed with/without the window will tell you how much of a load the window is putting on the motor.

The binding could be caused by dirt, by something having been bent during disassembly/reassembly, or by a manufacturing error with the new regulator -- holes don't line up or something. You could try loosening -- not removing -- all of the mounting bolts and then (carefully) operating the window. A problem with the regulator being twisted out of position should then get better.

I had problems like that years ago, putting power regulators in a car that didn't have them from the factory. Worse, the regulators were from a hardtop and went into a sedan. Each regulator arm had to be cut and rewelded. I'm still surprised that I was able to get them to work.

(2) The replacement regulator (you didn't say where it came from) might be a non-Mercedes cheapo replacement. You said "had [it] replaced," from which I infer that someone else did the work. Correct? If so, take it back.

(3) Partially broken wires or damaged/dirty connectors not allowing the motor to draw its rated current. This is potentially a fire hazard and should be checked immediately.

Jeremy

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"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
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