Oil filler neck leaks 35d 2011

[AnShk]

Seems like oil sips through the cap, but I do not know if it's because oil pressure is too high or any other reason?

I did check the cap sits tight, but still find seepage on the electric cables below.

Is it a common problem? What causes it?

[Thecastle]

Check your breather connections. The breather houses on the diesels get brittle with time.

[AnShk]

Originally Posted by Thecastle

Check your breather connections. The breather houses on the diesels get brittle with time.

I can not find breather hose where I find oil, find enclosed
Is it this hose? http://www.fixmyvw.com/bmw-ccv-breat...5d-and-x5-35d/

[serge1]

How did you determine the oil is coming from the filler neck?
Which electrical cables are you mentioning? On the photo, there's one plastic-encased cable and the rest are vacuum hoses.

Turbo feed lines are also right in that area. Are you sure the oil lines are not leaking? Take a closer look and report.

[335dsleeper]

If you’re pushing oil through the oil cap, your valvecover gasket might be on its way out.

6 of the 11 intake runners pass through the center of the valvecover. As the gasket ages it gets hard, brittle and won’t sufficiently keep boost pressure out. It will force oil out of the oil cap and out of the outer portion of the valve-cover gasket.

A member in the 335d section has similar issues as you and it ended up being the valvecover gasket.

[AnShk]

Originally Posted by serge1

How did you determine the oil is coming from the filler neck?
Which electrical cables are you mentioning? On the photo, there's one plastic-encased cable and the rest are vacuum hoses.

Turbo feed lines are also right in that area. Are you sure the oil lines are not leaking? Take a closer look and report.

It's probably not from the filler neck.
I drove another 1,000 highway miles and made it really hard.
Looked inside. Pretty much the same.
Green circle is where I think the oil can be seen.

[AnShk]

Originally Posted by 335dsleeper

If you’re pushing oil through the oil cap, your valvecover gasket might be on its way out.

6 of the 11 intake runners pass through the center of the valvecover. As the gasket ages it gets hard, brittle and won’t sufficiently keep boost pressure out. It will force oil out of the oil cap and out of the outer portion of the valve-cover gasket.

A member in the 335d section has similar issues as you and it ended up being the valvecover gasket.

I do not see any oil apart from the picture attached.

In N54 I had in the past the valvecover gasket leaked because I overfilled the oil. Hard to believe these gaskets should be changed ones in a while if temperature and pressure are normal.

[serge1]

Originally Posted by 335dsleeper

6 of the 11 intake runners pass through the center of the valvecover. As the gasket ages it gets hard, brittle and won’t sufficiently keep boost pressure out. It will force oil out of the oil cap and out of the outer portion of the valve-cover gasket.

I am failing to understand how leaky valve cover gasket would result in oil rising through cap.
First of all, for oil to rise through filler neck, valve cover would have to be completely filled with oil - that simply doesn't happen.

Turbo boost can affect pressure in valve cover if turbo seals are leaking, allowing either compressed air (compressor side) or exhaust gasses (turbine side) to slip by, through oil feed (and oil return) lines into crankcase, from there into valve cover. Our diesel engines are expected to have minor positive crank case pressure ("P" in "PCV").

Excessive crankcase pressure resulting in oil being pushed out of places, would manifest itself in oil pushed out of:
* Dipstick
* Turbo seals
* Gaskets holding oil (not vapors).

[335dsleeper]

I know you fail to understand. It’s because you are not familar with m57.

Look at an m57 valvecover. You’ll see where the top 6 intake runners go through the center of the cover. When the gasket gets old, it leaks allowing boost pressure to enter the valvecover, which causes oil leaks.

This is becoming more common as the engines age. I swapped mine a few weeks back because it was leaking. Few others have leaks from the fill cap when their gasket failed too.

Might want to search the 335d forum. It’s more technical than here.

So, it simply does happen

Originally Posted by serge1

I am failing to understand how leaky valve cover gasket would result in oil rising through cap.
First of all, for oil to rise through filler neck, valve cover would have to be completely filled with oil - that simply doesn't happen.

Turbo boost can affect pressure in valve cover if turbo seals are leaking, allowing either compressed air (compressor side) or exhaust gasses (turbine side) to slip by, through oil feed (and oil return) lines into crankcase, from there into valve cover. Our diesel engines are expected to have minor positive crank case pressure ("P" in "PCV").

Excessive crankcase pressure resulting in oil being pushed out of places, would manifest itself in oil pushed out of:
* Dipstick
* Turbo seals
* Gaskets holding oil (not vapors).

[335dsleeper]

M54 and m57 are completely different.

Originally Posted by AnShk

I do not see any oil apart from the picture attached.

In N54 I had in the past the valvecover gasket leaked because I overfilled the oil. Hard to believe these gaskets should be changed ones in a while if temperature and pressure are normal.

[serge1]

Originally Posted by 335dsleeper

I know you fail to understand. It’s because you are not familar with m57.

Look at an m57 valvecover. You’ll see where the top 6 intake runners go through the center of the cover. When the gasket gets old, it leaks allowing boost pressure to enter the valvecover, which causes oil leaks.

This is becoming more common as the engines age. I swapped mine a few weeks back because it was leaking. Few others have leaks from the fill cap when their gasket failed too.

Might want to search the 335d forum. It’s more technical than here.

So, it simply does happen

I see your point. I did not account for valve cover gasket also sealing the inside of the cover the runners (the 12 rings) channeling air from intake manifold (swirl flaps side):



So, it seems like a quick remedy for excessive pressure in valve cover from boost leaks is to delete swirl flaps:
http://www.fixmyvw.com/swirl-flap-de...5d-and-x5-35d/
Will require tuning to turn off swirl flap error codes.

[335dsleeper]

Swirl flap runners go into the head and not through the valve cover. Deleting swirl flaps won’t do anything for boost pressure leaking past the CCV.

There are 12 rings, 6 seal the boost pressure from the intake. The other 6 are holes for the Injectors.

Originally Posted by serge1

I see your point. I did not account for valve cover gasket also sealing the inside of the cover the runners (the 12 rings) channeling air from intake manifold (swirl flaps side):



So, it seems like a quick remedy for excessive pressure in valve cover from boost leaks is to delete swirl flaps:
http://www.fixmyvw.com/swirl-flap-de...5d-and-x5-35d/
Will require tuning to turn off swirl flap error codes.

[serge1]

Wishful thinking on my part. You are correct swirl flaps are the square openings leading straight to head.

Unfortunately, replacing the gasket requires pulling injectors...

Reason why this topic got my attention is because I am suspecting my turbo leak issues were in some part due to potentially excessive crankcase pressure.
So, I am reading up on anything crankcase related.

New LP turbo and newish (56k miles) HP turbo were put in. Today, reassembling intercooler and intake manifold after cleaning them of oil and crud.

[335dsleeper]

The m57 Turbos are very robust. If you had any issues with them, it was likely due to something else.

I swapped my hp turbo after I misdiagnosed it. It was my vcg and not the hp turbo.

Originally Posted by serge1

Wishful thinking on my part. You are correct swirl flaps are the square openings leading straight to head.

Unfortunately, replacing the gasket requires pulling injectors...

Reason why this topic got my attention is because I am suspecting my turbo leak issues were in some part due to potentially excessive crankcase pressure.
So, I am reading up on anything crankcase related.

New LP turbo and newish (56k miles) HP turbo were put in. Today, reassembling intercooler and intake manifold after cleaning them of oil and crud.

[serge1]

Originally Posted by 335dsleeper

The m57 Turbos are very robust. If you had any issues with them, it was likely due to something else.

I swapped my hp turbo after I misdiagnosed it. It was my vcg and not the hp turbo.

what were the symptoms leading you to believe it was the HP turbo?

[335dsleeper]

I had a lot of blue smoke when cold, smelled oil burning. When I looked under the hood, the HP turbo had a ton of oil around the turbine housing and compressor housing. You could see where the oil was coming through the compressor cover.

Even though I knew it was impossible for both seals to fail at the same time, I swapped the HP turbo. Shortly thereafter the smoke returned.

I ended up swapping the vcg and all is well. Essentially, the rubber gaskets gets hard with age. When cold, it would pressurize the crankcase sending oil through the turbo seals. The oil went in the exhaust and into the intake etc. it was a mess.

It’s been perfect since and I have just under 211k miles on my 35d.

[serge1]

That's exactly the symptoms my 125K miles x5d has:
* Blue smoke lasting 10-15 seconds when cold. I can start cold, let run for 15 seconds for smoke to dissipate, start again, smoke would return. Basically, starting/stopping every minute when cold results in blue smoke until warm. Smoke returns when engine cools off enough after couple hours.

* Oil leaking on compressor side, severely. On turbine side, layer of soot - potentially leak there, too.

* I have ProVent 200 installed and it does an excellent job filtering blowby - return pipe is nice and clean. So, I know the oil in the intercooler not blowby.

The LP turbo was definitely bad. Lots of shaft play in all direction. After disassembly, shaft shows discoloration, characteristic of oil starvation. Oil feed lines did leak a while ago and had to be replaced.

Was researching the blue smoke topic for a few months now but never came to a conclusion - symptoms didn't quite match my case. Everyone is pointing in 2 directions: turbos and injectors. But, the symptoms never really match my case - smoke only when cold.

I am really having 2nd thoughts about starting driving it before taking care of valve cover gasket. It seems quite likely I am in same situation you were.

Also, while replacing turbos, went with delete kit and opted in for DOC. It would be shame to get the new DOC poisoned with turbo oil.

I think I know a guy who may have injector pulling tool.

Speaking of injectors, is it a good idea to clean them while they are out? Not sure I can afford $500 x 6 so soon after this "delete + turbo replacement" project that went over time and budget..

[serge1]

Found the E90 thread. Thanks.

P.S. AnShk , sorry about hijaking the thread.

[AnShk]

Today I got yellow engine light warning while driving.
Checked it's $7E8 and &7EC errors. Checked engine cover and found oil from both left and right. Not that it drips during parking, but oil is there.

Oil level seems as normal, I do not see any changes.

I found my front rims oily too, guess it's from oil leak?

[AnShk]

Originally Posted by AnShk

Today I got yellow engine light warning while driving.
Checked it's $7E8 and &7EC errors. Checked engine cover and found oil from both left and right. Not that it drips during parking, but oil is there.

Oil level seems as normal, I do not see any changes.

I found my front rims oily too, guess it's from oil leak?

I opened the engine cover and this is what I see.
Oil is mostly on the driver's side.
One drop can be seen on one of the hoses.

[AnShk]

BTW, car just hit 70K. It was driven by a woman before, mostly city drive, plus used as a tow truck ones in a while. I drove it hard on a highway and this is what happened.

[serge1]

That has to be oil leaking out of intercooler. May have been quietly sloshing in there during previous owner's time, then you driving it hard introduced more boost than normal into intercooler. The seals (designed to hold pressurized air, NOT oil), must have finally gotten deteriorated by the oil and allow it past.

The seals are #2, #3, #13, #14 here:



I had a similar issue around 40K miles.