630i sport 2010 N53 heavy oil consumption

[viperbluecerb]

Bought my 630i at the end of last year, taking a punt on a late Sept 2010 car in great condition 70K miles but no service history.

Unfortunately she is consuming oil at a rate of about 1 litre per 400 miles. I've changed the PCV valve which required a completely new rocker cover and destructive inspection of the old unit revealed no problems. Oil consumption continued.

Compression tests around 130psi across all cylinders. Plug in cylinder 6 badly fouled and covered in fuel/oil.

In the process of stripping down the engine to remove the head which should help reveal the cause, perhaps damaged bores/rings or valve guides/seal problems, we'll see.

I'll post some pics as things progress.

Edited by viperbluecerb on Monday 30th May 11:25

[viperbluecerb]

Some updates in this thread. Possible manufacturing defect, doesn't look like the bores have been finished correctly.

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

[viperbluecerb]

bmwmike said:

Does anyone know if the n52 cylinders use the same material? It looks like ceramic. All the n52 bores Ive seen online look like metal.

Yes, the N52 is the same aluminum/magnesium construction and uses alusil as the bore surface as in the N53.

[viperbluecerb]

Update on this thread:

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

5 out of 6 of my injectors are trash (leaking) and I suspect could be the cause of high oil consumption.

[viperbluecerb]

bmwmike said:

OP - Just curious if you noticed any puffs of smoke on startup, especially after it had been sat for a few days?

I haven't tbh