83-240D: I have only listened from the drivers seat. I can only get it to squeal if I turn on the lights, heater fan, etc. No noise at idle, just when it's reved up. It seems so loud with the hood open, door open, sitting in the driver’s seat, that it would be hard to localize. Good idea, I’m going out to try it today.

JJ: I checked the weep hole at the top and it is dry. The exposed part of the pump, where it bolts up is rusted, but looks like it would be, as it is just bare metal. Car has no rust as a general statement.

Other maybe clues are:
1. The radiator is never perfectly full. I do not have a reservoir, just fill to the little line inside the neck. It never stays right up to the line. Gets about 3/8” below the line, but never gets any lower.
2. When I got the car it did not have a fan shroud. It does now.
3. If I grab the big, black cylinder part of the shaft behind the fan, but in front of the pump, it does not seem like it wiggles, but I can see the tension on the belt change. At this point I’m shoving it hard enough to move the whole front end of the car. The belt tension is changing for sure.

Thanks,

Clay

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2002 E320 Sedan 93K Designo Mocha Black Metallic!
1995 E320 Wagon 205K Black Wagon
1982 240D 183K SloPoke

I believe each of these cars are the final production year for that model.