ihaveaquestion

Well, video is worth a thousand words so here you go:


It's on the passenger side (US model) of the engine bay. It smokes after the car has been sitting for a while but makes no smoke after the first 15 mins.

I am very bad at identifying parts but I think I see the exhaust pipe underneath a black connector. That's approximately where the smoke comes from. Is there a known issue with this area of engine bay?

My best guess is that there is a leak nearby so when the exhaust gets hot it burns off whatever fluid dripped onto it. I found a wet spot in that area too before it got burned off.

So can someone with knowledge help identify the plausible cause for the smoke? Much appreciated.

xsever

Can you remove the plastic engine cover so we/you can see better and exactly where the smoke is coming from? You can search on youtube how to remove the plastic engine cover. It's very easy.

MBENZTECH

It's the centrifuge cover leaking oil onto the exhaust. Also known as the oii and air separator. Replace it along with all the camshaft plugs.

timlippold

Ditto. That was my issue. Feel around oil separator for leaks. Can also shine flashlight around back of engine to look for them around plugs.

Adi-Benz

https://mbworld.org/forums/c-class-w204/654685-diy-centrifuge-cover-oil-separator.html

ihaveaquestion

Thanks much!

I will have a weekend project to do now

ihaveaquestion

So is there one on each side of the engine?

https://photos.app.*******/Yj23qDS98FRJk2Ea8

The first pic is on the driver's side, the other two are on the passenger side. I am about to place an order for parts.

Btw, youtube video shows 6-star nuts but mine are screws. Wonder why.

Is this the right part?
https://www.fcpeuro.com/products/mer...ebi-2720100631

Adi-Benz

Yes that's the right part, your pictures don't work btw.

gamma300C

My 57K mile C300 has started to give off a mild burning oil smell in that same area since the temps have been in the teens when starting up...a finger swipe around the air/oil separator shows no obvious oil, just a minimal greasy smear but sure that this is the source as in your case. I already changed out the cam plug on that side months ago. Thicker cold oil with a higher initial start pressure I assume is the reason since on warmer days I don't smell anything. I have been too lazy to remove the under cladding to see if there is another leak area.

ihaveaquestion

Honest to god! Anything involved with working so closely to the back firewall is just calling for pain!

First it was the coolant temp sensor and now this! Took me 4 hours to take 4 screws off. Now they are off, I don't want to put them back on because I have stripped a couple of them in the process. If anyone know the correct size of the screw ( not nut) or where to get them please let me know.

A tip for future DIYer - Small adjustable wrench on a T30 screw bit will work wonder...

Peace.

ihaveaquestion

Btw, I notice the new part has more rubber in the middle:

https://photos.app.*******/53EVTNQ7pW5bXQRY6

Is this normal? I find it a little hard to install the new part due to more rubber in the middle...are we supposed to force it in?

MBENZTECH

Yes, that is normal. It is a brand new seal. Just center it and push in without damaging anything.

Kelvin Bellrose

Could this part be a source of a vacuum leak as well as spew oil?