[Alexbmw320d]

I was doing and oil change yesterday on my f30 320d N47. Underneath I noticed the underbody covering had a stain of oil and I could see that the sump was wet with oil. I dipped the car not only last week and it was still up around the max mark.

Anyway I looked in around the engine bay and seen beneath the filter housing was wet with oil and in around the oil cooler also had oil around it. Just thinking that it's possibly the gaskets that are the cause of the leak? I've attached a picture if anyone else would care to have a look and see what they think.
Thanks

[Eddamoo]

I would give the whole lot a damn good clean with degreaser/brake cleaner to get it looking clean and then check it after a drive. You should then have an easy to identify leak. With that much oil everywhere you'll struggle to find the culprit.

Also a more zoomed-out shot would be useful as many wont know where that stuff is on a 20d engine.

[Alexbmw320d]

Good idea I never thought of that. I will get it cleaned up first and take it for a drive and see.

[Alexbmw320d]

Tried cleaning but not easy with everything in place. I am going to go with my hunch and replace the gaskets. I can't see where else it may be leaking from. I've ordered the 2 gaskets circled from the parts diagram. Hopefully this solves it.

[erickonphoenix]

The #6 gasket is the common failure. You also should inspsect the valve cover gasket for leaks as well. Those jobs don't overlap so if you need to do the VCG you can just do it later.

[TurboWeasel]

Could be shrunken/hardened gaskets or O rings, or it could be sloppy oil changes as most mechanics don't care about letting oil filters dribble onto the engine. As recommended, clean the area first and monitor it.

Nearly all engines with engine block to accessory interface gaskets / o rings suffer from ageing leaks. Just one of them things. As above, number 6 is especially prone to shrinkage because it's cheap shitty butyl rubber instead of decent Viton. Number 5 not so much as it's gasket.

If your car has the ZF8 auto, you might lose a bit of trans fluid when dismantling the heat exchanger.

[Alexbmw320d]

The car had 172k miles now and I assume it's on the original gaskets so I can understand they are likely perished by now. I've ordered bother gaskets I think it's better to change the both of them if I'm in that far and for both of them it was only 35/40 quid.

The cars a manual so it should be easier than the automatic transmission. Just hoping I can do the job with the air intake in place instead of having to remove it. I will check the rocker cover gasket again although I couldn't see anything obvious the last time I looked.

[Alexbmw320d]

Originally Posted by erickonphoenix

The #6 gasket is the common failure. You also should inspsect the valve cover gasket for leaks as well. Those jobs don't overlap so if you need to do the VCG you can just do it later.

Done this job at the weekend. You were right gasket #6 had failed in one area and it was flattened out. Overall it was a relatively easy fix and saved me going to a mechanic. Cost me about 50 bucks all in.