3.0D black oil at top of coolant expansion tank and radiator UPDATED

[LVR]

Hello all

Kind of stumped. I took off the air intake cover to finally change over the aux fan today and found black oil all up around the intake and over the coolant reservoir / expansion tank.

I cannot see where it is coming from.... but it is all around tank only.

Does anyone have any suggestions?


Cheers

[Ohsoslow]

Your intake charge pipe looks to have a split in it?! If so, that will likely be blowing air/oil out under load.

[LVR]

Hmm. ok, if that's the case, is that amount of oil in the intake symptomatic of bearings?

The car has 160k on the clock.... blows a bit of white smoke on start up and reeks of diesel smell when running...

[Ohsoslow]

Depending on the year, they have a filter in the rocker cover to catch oil vapour from crankcase etc. have you checked/replaced that?

[wpoll]

It's worth using the newer "vortex" design oil separator if replacing it. The older "loo roll" design is prone to clogging and causing high crankcase pressures.

Bad on right, good (new) on the left...



More info here... CHANGING 3.0d breather assembly

But I can't see how this would be related to the oil on the radiator tank etc. Unless the crankcase is so pressurised it's blowing oil out a gasket interface somewhere...

[nice1guv]

Take the cover off the top of the engine and have a good look around.

Oil over that side of the engine is a bit odd as most of the intake/turbo etc is on the other side.

That kind of oil does look like dirty diesel intake though, the kind you find in the turbo air lines etc.
Try having a look around the intercooler connections.

Another place to look is at the EGR hoses at the top front of the engine, this is about the closest air/recycle lines to the radiator tank.
If your EGR has never been cleaned, I would also remove and clean it, as it is sure to have a lot of crude in it.

[nice1guv]

Any update on this LVR?

[Nathanw]

Originally Posted by LVR

Hello all

Kind of stumped. I took off the air intake cover to finally change over the aux fan today and found black oil all up around the intake and over the coolant reservoir / expansion tank.

I cannot see where it is coming from.... but it is all around tank only.

Does anyone have any suggestions?


Cheers

The first pic tells it all. I had the same problem with my x3.

You have a split in your upper boost pipe that connects to the egr valve on top. It opens up more under boost pressure but you can see the crack in the pic. It is normal for a bit of engine oil to pass through that pipe at your mileage.

Once I replaced the part my car used less oil between services. I am not sure of the technical reason why though. Maybe the split boost pipe causes a vacuum which draws oil from somewhere? But that is definitely your problem. The boost pressure causes the oil to spray out quite far and that's why it got all the way to your water resorvoir.

[LVR]

Hello all

Thanks to you guys here I set about a few things regarding the oil leak and hose, which led to other things lol....

It had begun to blow some blue smoke, and if you floored it off the lights a big cloud of diesel smoke was present for a moment as well as a very bitter smell... so I figured time to do some additional maintenance beyond what had been done at the servicing.

For other 3.0D owners here, this is what happened...

I discovered that all the glow plugs were RS so they got replaced. It had been starting no problems and as we live in a warmer climate I wasn't bothered about them. I figured as it was getting some extra TLC to sort it I may as well attend to it also.

I then found that the air inlet filter element was pretty badly gunked up, so out it went also.

Next to do was the CCV. Ordered the parts and no probs to install.

I ended up ordering the wrong inlet hose to replace the split one so after the above was done it was time for a drive...

MAJOR change in the NVH... idled a LOT smoother, lost a heap of vibration, gained power and lost the pungent smell. The blue smoke was barely present and only then on start up.

Finally got the new turbo inlet hose in and installed today. Looked at the old one and didn't realize how bad it was under load.

While installing it saw how much oil had been getting through the CCV and the amount of carbonized buildup from the exhaust gases in the EGR valve.

Cleaned it out and then had my indy reset the trans and engine adaptations... It was losing quite a bit of pressure through the split and causing the blue smoke.

WELL... more boost and even more power..... no smoke no matter how hard you stomp on the loud pedal. Much more drive-able and has lost that 'truck feel' from the engine. Smoother idle and less noise.

Wifey is VERY HAPPY and well pleased with the result (it's her daily driver). "It's a completely different car"...

thanks guys for the advice and help.

Hope this helps others...

Cheers

[wpoll]

Thanks for the update!

I have a service due this week and will be attending to the inlet system too, although I don't have any major issues showing. I have new gaskets for the inlet pipe to EGR, EGR body etc. and I'll clean out the EGR, the inlet temp sensor (which is rather oily) and anything else I can get to in that area. Along with new oil, oil filter and fuel filter, I'll also do a quick check of the exhaust manifold with a USB inspection camera (making sure I have no cracks - yet).

*edit* I checked it and it IS cracked! - https://xoutpost.com/bmw-sav-forums/...ml#post1137542

All of which is required basic servicing needed on these old girls. A little TLC and they just keep giving.