Oil Separator Failure?

[trahsub]

Helping a friend with a few items on his low mileage 2012 E92, and when pulling a few things we noticed residue on the driver's side head. Appears that it's coming from the oil separator; are these known to just get jammed up? Or could this be something else?

Simple replacement once plenum is off? I've read about ensuring the mating surface is clean and paint doesn't chip off the valve cover. Thanks.

[amrazM]

could be cracked, plenum could have not be seated all the way, many explanations, smoke test it for an answer.

[SYT_Shadow]

to replace, just remove the plenum and be careful pulling them off. Very simple

[trahsub]

Great, thank you. Cheap enough to just replace as I'm thinking a previous tech may have cracked when removing plenum (since this is side with the pesky rear breather hose connected.

Appreciate it.

[TX]

It's very easy to replace. The bolts are TTY so officially they are one time use, but it's up to you if you want to replace them or not. I'll list the parts below.
Torque: 4Nm joining + 45* rotation.
Oil separator #11157848155 (2 per car)
Torx screw #11417526315 (8 per car)
Gasket #11157838369 (2 per car)
O-ring #11157838370 (2 per car)

Part quantities are for both sides.
Cheers!

[pbonsalb]

Do they fail? Mine have 108k miles and they seem to flow fine. They are just baffles. There aren’t parts to fail inside. Seems like you would need a lot of miles to get enough oil residue in there to block a passage.

[drrust]

I had to replace one of mine because it had cracked around the seam. Pretty easy replacement.

[trahsub]

Originally Posted by pbonsalb

Do they fail? Mine have 108k miles and they seem to flow fine. They are just baffles. There aren’t parts to fail inside. Seems like you would need a lot of miles to get enough oil residue in there to block a passage.

I think it's cracked due to previous work from a non-TLC mechanic that probably wrestled to remove plenum. It's on drivers side where that rear vacuum hose connects, probably popped up and damaged the separator.

[ha9981]

Originally Posted by TX

It's very easy to replace. The bolts are TTY so officially they are one time use, but it's up to you if you want to replace them or not. I'll list the parts below.
Torque: 4Nm joining + 45* rotation.
Oil separator #11157848155 (2 per car)
Torx screw #11417526315 (8 per car)
Gasket #11157838369 (2 per car)
O-ring #11157838370 (2 per car)

Part quantities are for both sides.
Cheers!

It's a common misconception that fasteners on these cars are TTY due to torque angle. It's not true.

Did you check TIS to know they can't be reused? Or is it based on torque spec?

[trahsub]

Pretty certain the o-ring and gasket come with the separator when you order. As per pictures. Confirming this to be the case?

[drrust]

Originally Posted by trahsub

Pretty certain the o-ring and gasket come with the separator when you order. As per pictures. Confirming this to be the case?

Yes, the gasket and O-ring come with it. If you're considering replacing the valve covers in the near future, the valve cover kits include the separators. But that increases the costs by orders of magnitude.

[TX]

Originally Posted by ha9981

It's a common misconception that fasteners on these cars are TTY due to torque angle. It's not true.

Did you check TIS to know they can't be reused? Or is it based on torque spec?

I based it on the statement that says "replace screws" next to the torque spec. I may be incorrectly using the term TTY, if they are not. I'll just say replace screws.

[ha9981]

Originally Posted by TX

I based it on the statement that says "replace screws" next to the torque spec. I may be incorrectly using the term TTY, if they are not. I'll just say replace screws.

TTT = Torque to Turn
TTY = Torque to Yield

If the spec is TTT with angle it doesn't necessitate it is TTY. This is misinformation. A bolt can be TTY regardless of its torque spec, it just has a spec high enough for the bolt that causes it to yield, hence cannot be reused.

So here are the ones that you certain definitely MUST NOT REUSE:
- blue painted dot on head
- aluminum but no painted dot
- specific engine bolts like rod bolts

TIS uses two terms, "renew" and "replace". You find "replace" used on pretty much every bolt. So I can't imagine that meaning TTY.

I suspect "renew" means TTY but I am not certain as a lot of the control arm bolts have "renew" yet I can't imagine every Indy shop does so when they disconnect the control arm. Maybe "renew" is used as a recommended to replace but does not necessitate the bolt has yielded at it's torque spec.

The tech at the dealer said to look for the blue dot / aluminum or see if the bolts are listed as "required" under the job in BMW tech manuals.

In a torque spec on TIS for the steering spindle to rack (32 31 1AZ) it says "No retorquing permitted" perhaps this is how they clarify it is TTY.

If someone who worked as a BMW Tech can help out clarifying how to tell for certain it is TTY from TIS, that would be much appreciated.

[akkando]

I definitely reused these bolts when I removed the separators. RIP.

[TX]

Originally Posted by ha9981

TTT = Torque to Turn
TTY = Torque to Yield

If the spec is TTT with angle it doesn't necessitate it is TTY. This is misinformation. A bolt can be TTY regardless of its torque spec, it just has a spec high enough for the bolt that causes it to yield, hence cannot be reused.

So here are the ones that you certain definitely MUST NOT REUSE:
- blue painted dot on head
- aluminum but no painted dot
- specific engine bolts like rod bolts

TIS uses two terms, "renew" and "replace". You find "replace" used on pretty much every bolt. So I can't imagine that meaning TTY.

I suspect "renew" means TTY but I am not certain as a lot of the control arm bolts have "renew" yet I can't imagine every Indy shop does so when they disconnect the control arm. Maybe "renew" is used as a recommended to replace but does not necessitate the bolt has yielded at it's torque spec.

The tech at the dealer said to look for the blue dot / aluminum or see if the bolts are listed as "required" under the job in BMW tech manuals.

In a torque spec on TIS for the steering spindle to rack (32 31 1AZ) it says "No retorquing permitted" perhaps this is how they clarify it is TTY.

If someone who worked as a BMW Tech can help out clarifying how to tell for certain it is TTY from TIS, that would be much appreciated.

I was only trying to help...not start a war over bolts. I will always be happy to learn something new.
I just dug through my garage to find my old bolts from when I replaced my valve covers a year or so ago.
They are:
1) aluminum bolts
2) with blue painted heads
So I don't know how that lines up based on your above rules. I'll yield my TTY statement to someone who knows more than I do. The TIS said replace bolts. Over the years I've gone by that and maybe I've replaced more bolts than I should have. Who knows.
Cheers.

[ha9981]

Originally Posted by TX

I was only trying to help...not start a war over bolts. I will always be happy to learn something new.
I just dug through my garage to find my old bolts from when I replaced my valve covers a year or so ago.
They are:
1) aluminum bolts
2) with blue painted heads
So I don't know how that lines up based on your above rules. I'll yield my TTY statement to someone who knows more than I do. The TIS said replace bolts. Over the years I've gone by that and maybe I've replaced more bolts than I should have. Who knows.
Cheers.

Just trying to help.

Sorry it offended you.

As stated aluminum bolts with or without blue dots are never to be reused. Blue dots are a marker for don't reuse. So you did right with those.

The rest I'm pretty confident can be reused. Excepting rod bolts and other bolts that may have multi install torque procedure to stretch.

[TX]

Originally Posted by ha9981

Just trying to help.

Sorry it offended you.

As stated aluminum bolts with or without blue dots are never to be reused. Blue dots are a marker for don't reuse. So you did right with those.

The rest I'm pretty confident can be reused. Excepting rod bolts and other bolts that may have multi install torque procedure to stretch.

Not offended in the least. Just wanted to make sure I wasn't giving bad advice and would be happy to be corrected any day. That's the whole point of this community is to share information. If it is wrong and needs correcting, I'm all for that.
No worries.

[jvictormp]

Originally Posted by ha9981

Just trying to help.

Sorry it offended you.

As stated aluminum bolts with or without blue dots are never to be reused. Blue dots are a marker for don't reuse. So you did right with those.

The rest I'm pretty confident can be reused. Excepting rod bolts and other bolts that may have multi install torque procedure to stretch.

I've heard the rod bolts could be reused if they are ARP, is that right?

[ha9981]

Originally Posted by jvictormp

I've heard the rod bolts could be reused if they are ARP, is that right?

Yes ARP ones.

OE BMW no, those are stretch bolts. Single use.

[Garner1]

Hi, new member here.. I am looking for info on the oil separator, I think mine may be going (gone) bad, I am getting oil on 2 plugs near the separator, they look pretty bad after 2 weeks of driving and the oil level drops pretty quickly when driving hard. I have been replacing them with new ones. I hope its the separator and not some bore issue. Car idles fine, however I can smell a faint smell of gas when its running and I am near the tail pipes...

Help

[jvictormp]

If there is a bore issue, I think you'll detect it with a compression test.

[Garner1]

The only reason I mentioned bore issue is someone said it could be bore scores causing the oil leakage plus allowing the plugs to get coated...