GL320 - believe this metal ring should not be there should it? Can't find it in ETK. I did not reinstall with the new set of filters.

 

I would look in ETK for similar items upstream of the air box. That is, it was probably sucked in

could be of interest if you haven’t already also to view official Mercedes procedures for diesel air filter change ... which include a computer reset.

 

Clearly, it's the tensioner ring for the blinker fluid expansion reservoir that is upstream of the air filter housing. It is a special forged magnesium piece that is strictly used on some early OM642 engines. Without it installed, your engine will most likely suffer from a domino effect of leaking oil cooler seals, excessive timing chain wear, and before too long black death will occur. I hear they are on back order indefinitely and, judging by how that one is bent, it is not reparable. You may be able to find a machinist who has access to a forged magnesium billet. They may be able to machine the new part but it takes a special diamond and unobtanium bit to ensure it is machined correctly.









Looks like road debris to me.

 

I'm afraid you are behind the curve....unobtanium is freely available now due to COVID restrictions!

 

Normally, I would agree with you but don't forget these have ripoffeum too. Without the ripoffeum, they may not last. It is said, the part uses a blend of 75% forged magnesium, 32% unobtanium, and 24.64623578156121% ripoffeum.

 

Yes! That's what it is. I am so glad to have finally tracked that down. That blinker fluid has been messing up my driveway for months now. Well, I think I have hit two stones with one bird here.

 

Actually, that foreign object is 100% Chinesium.

 

Touché...... as indeed most things are these days!