W123 Frt Whl Brgs - spring in spindle cap?
 

Check your front wheel bearings!

The original owner had written on the inside of the wheel covers the last service: 1989, 59K. Wow, 21 years ago! So with 118K I thought it might be prudent to pull the rotors and check the bearings. Good thing, both seals were leaking and grease was getting to the brake pads, and the grease looked like dirty maple syrup. What a mess inside the rotor housings, both sides. Fun day of degreasing, regreasing, and putting everything back together with synthetic grease - nice stuff. Took the rotor dust shields off and degreased those too, scrubbed both sides, and touched up with a bit of rattle-can. Blue lock tight on the dust shield and caliper bolts. Nice and clean in there now with new grease and seals.

What is the little copper spring on the inside of the spindle cap???
One of mine was broken, other was fine. I have never seen these before. Found 'em on epc parts diagram.

It's for radio noise suppression. They prevent the build up static electricity which makes a noise on the car radio. mercedes Have been installing those for at least 60 years.

Do you by any chance have a MB part number for them? Mine are bust too...

(I had a similar problem with my front wheel bearings - and I've just done the rear ones too)

A2015470085 Contact spring inside front spindle cap

Used during the days of AM and/or shortwave only. FM does not suffer from this problem.