Clk55 burning oil?

[Hooblah]

I've recently acquired a 2000 clk55 and I've noticed that it smells of burning oil in the cabin when I have the fan on, and a week or two ago it developed a slight misfire at idle.
I can't see any visible smoke behind me during day-to-day driving, but I did leave a great puff of smoke behind me when I hit the kickdown a couple of days ago.

There are no leaks from the rocker covers or anywhere visible, no traces of oil on the manifolds either. This leads me to believe that it's burning oil.

The car's done 110k so it's well within its service life. There's a stack of service history to go with it and it appears to be well looked after. It seems unlikely that the rings need replacing but the symptoms point to that.

What are peoples thoughts? Has anyone experienced similar?

 

[GordonTarling]

How much oil is it actually using? If it's burning oil, the smell of that would normally be left behind and you wouldn't smell it in the cabin unless you were reversing. If you can find someone (an indy) who really knows those engines, then get them to have a good look around for signs of a leak.

 

[Hooblah]

No idea how much it's using as I haven't checked. I haven't had the car long enough for it to be an issue.

I can smell oil after stepping out of the car. Its not a strong smell, but there is a slight whiff.

I don't need an indy, I'm competent enough to do all my own work.

 

[BlackC55]

Those engines do use a bit of oil. The limit is 1L/1000KM (600 Miles).
If you can smell burning oil then I am sure you will have a little leak. Check around the bell housing as its common for the rear main seal to leak as well as the RC gaskets as you mention. Also the plate that hoses the seal has oil galleries behind it that block up and cause the engine to breathe heavily and use oil enough so it smokes.

 

[Hooblah]

Thanks for the info.

What is the purpose of the oil galleries?
Is there a way to clear the blockage without removing the gearbox?
If its something to do with crankcase ventilation, will fitting an oil catch can help?