N63 oil leak,,,,we have been finding out that the turbo oil return housing gasket will start to leak,,,,and leak down the rear of the engine and around the transmissions,,,,,,which then looks like the rear of the oil pan is leaking,,,,,but it is not,,,,,,in the last pic the turbo oil return housing is under the heat shield for the turbos,,,,,recommend if any turbo work is done replace that housing it comes with the gasket
bmwtechnician 
how many hours is this job?
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I don’t know which oil leak on the N63 you were looking at,,,,the N63 oil pan leak is about 9 hours,,,,,,and has about 40k miles,,,,,,,or the turbo oil return housing also takes about 8 to 9 hours,,,,that car had about 50k miles,,,,I hope this helps
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i have a leak between engine and transmission but looks like is more rear main seal. From top i can see wetness around oil pipes on cover flange but is hard to say. I am planning to take a tranny out to confirm or is ther a better way to see it?
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No there really not a easier way to find the oil leak,,,,the good thing about removing the transfer,,,,is you can inspect the rear main seal,,,,and see if the oil leak is the rear seal or coming from up above from the engine.
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750 LI 2011y
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Hi, i am also facing the same issue, what is the cost of repairing the same….?
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I don’t know the cost of repairs,,,,as BMW tech we don’t see the repair bills,,,,,I can tell you it pays about 7 hours labor plus parts.
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Does this have a bad oil burning smell to it? I have a smell in my 2011 550 N63 and the dealer can’t seem to locate it. I can smell something burning every time I park in my garage. I can also smell it when I sit at idle, or literally smell the engine. Dealer thinks I’m nuts. But others can smell the same smell. Someone suggested that the turbo coolant lines can cause that smell shortly before they fail. Car has 103K on it.
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If the coolant lines have failed,,,,you should have a sweet smell from the coolant leaking on the hot engine.,,,,did anyone check the main coolant resvoir and the little coolant resvoir for the turbos if they are low on coolant.
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I’ve checked the main one. Where’s the little one?
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In order to replace the oil return housing gasket what other parts needed to be replaced once you reassemble? Could you step me through what all you had to remove?
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It pretty basic,,,remove both air filter housing,,,remove charge pipes,,,remove turbo coolant hoses,,,remove catalytic converter clamp,,,push catalytic converters out of the way,,,just start removing all the brackets that get in the way so you can gain access to remove both turbos,,,,you might want to replace the oil return metal pipe ,,,because they might crack when you pull them out,,,I know I forgot something,,,it’s easier when it’s in front of me and I am doing it myself,,,,just take your time ok.
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Did you have to remove the alternator and the fuel feed line to get the heat shield off to access this oil return?
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Yes and also that by-pass coolant hose
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How important is it to cap the fuel lines? That tool will be hard to find…
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It’s not that important,,,,don’t worry about it
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The nuts holding the exhaust manifolds look pretty rusted. The docs say to coat with copper grease after installation, but mine are pretty dry. Is there a technique to get those off without breaking a bolt? I’d hate to get this far and not be able to replace the seal on the turbo oil return.
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Spray them with WD40 will work just fine,,,,or any other lube spray
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These came right out with some pb blaster. In fact, 4 of the bolts came out instead… Now that I have everything off, any advice on putting the new gasket on? Should I coat the rubber with oil prior to bolting it down? And what about the gaskets on the turbos when I put those back on? Any tips?
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Nothing special about putting on the new gaskets and oil rings,,,,,yes you can put alittle oil on the o-ring to make easier to put together,,,,you can alittle anti-seize on the exhaust studs
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Just finished this job (thanks for the helpful comments on my questions). Here are my thoughts for any other DIY-ers out there:
You can do it but you need NewTIS to give you the torques and the steps. I ordered new oil lines to and from the turbos, and pureturbos did the rebuilds. The hardest parts were putting the turbos back on (v-clamps suck) and putting the stupid catalytic converter heat shields back on (there is a bolt under there that is just impossible to reach). I also took tons of pictures along the way, which helped when I put the fuel line on the wrong side of the bracket on the alternator.
I would guess that it took me 25+ hours over several weeks, but I’m still learning to wrench. I had a helper for some steps. I replaced the CCV lines (BMW will cover those) and the aftermarket coolant bypass hose was $25 and looks much more robust than the OEM.
Starting the car was one of the most terrifying things in my life, because there is air in the fuel line that takes a bit to work out and so the car runs rough and throws all kinds of codes that you’ll need to clear out afterwards. I still have a little smoke from the protecting coatings burning off (and the PBlaster that I used to pull the exhaust manifold nuts also got everywhere on the manifolds, and that is burning off too). But it is purring like a kitten now. A very expensive, turbo-charged, fuel injected kitten.
All in all it was a very fun project if you don’t mind the abject terror when you start the car for the first time. There was a lot of tar buildup in the middle exhaust ports on each side, so I will need a full valve job and walnut blast in a few years. Hopefully the car will run fine until then.
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Good job,,,,I understand that heat shield bolt in the back,,,,that bolt is a pain in the butt,,,,,lol,,,,,even for me when doing a big engine job and starting it up for the first time is alway scary,,,,,I always say my butt tightens up while starting up a big engine job,,,,lol,,,,,,good job sound like everything worked out
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The engine is still running great, but I think I have an exhaust leak, because I can smell exhaust at stop lights. Nothing while I am driving. Any idea where it might be? I renewed all gaskets at the turbos and the bottom of the cats, as well as at the exhaust manifold (my exhaust manifold originally had 8 plates, but apparently the replacement was these double-sided gaskets; I didn’t put the plates back on, just the double-sided gaskets).I’m hoping it is just at the turbo exhaust, because I really don’t want to get down into the exhaust manifold…
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No idea where it’s coming from,,,it’s not a common problem,,,you should remove the heat shield and see some kind of black soot where it leaking from,,,,,,Merry Christmas
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I am looking into doing this over the Chrismas weekend. What else should I replace as the preventive measure? I am thinking to replace gaskets under the turbos and on both ends of oil return lines, should I? Anything else?
Thanks,
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You should also replace the water by-pass hose which goes to each cylinder had and goes by the alternator
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Here is my DIY on my replacement:
http://www.bimmerfest.com/forums/showthread.php?p=11768225#post11768225
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I finally did a smoke test of my turbos to try to find the exhaust leak, and I think the wastegate diverter seal is bad:
It looks like I’m going to have to pull 1-4 side turbo out again. Do you think I can get away with just loosening the catalytic converters rather than pulling them off?
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I have heard of some guys doing,,,,but I have yet to do it that way,,,,I don’t know if that slight leak is your exhaust leak,,,,I don’t see any black exhaust on the wastegate arm,,,,did you run the engine with the heat shield off and see if any exhaust comes out of that wastegate shaft,,,,you should be able to feel some exhaust leaking at that area,,,,I just want you to be sure that’s your problem before you tear it apart again
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I tried it briefly today (I had the airboxes plugged in but kind of positioned off to the side). The engine changed RPMs and I got worried so I shut it off. Is it ok to run without the airboxes on?
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Yea it’s kind of hard to run it with the air boxes off and disconnected ,,,,do you smell the exhaust smell coming from the top of the engine area
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I looked again today and the jet of hot exhaust coming from that location was so hot that I burned my hand LOL. So that is the problem. Hot things hurt! The engine was cold and only ran for like 20 seconds before I tested it, and we didn’t feel any other hot areas around the engine. I’ll have to work with the guy who rebuilt the turbos to get it fixed.
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When I take the turbos off, do I have to renew the seals when I put them back on? I just put them in a few months ago. Or are they like toilet seals and can only be seated once?
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Lol,,,,BMW says to replace,,,,but you should be ok
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need help with this code 118501 Mixture control 2: Fuel-air mixture too lean, large deviation. What are the common symptoms to check for on the n63?
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So bank 2 is running lean,,,could be a air leak somewhere ,,,,,vent pipe could be broken,,,,need to have the intake system smoke tested to start.
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Hi there, working on this job right now. Do the catalytic converters need to be completely removed? I’m at the point of removing that rear heat shield with the very hard to reach bolts but am unsure if the cats need to be physically removed from the engine in order to get access to the oil return housing. 2013 X5 50i.
Thanks! This is a great site!!
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Yes the cats need to be removed and the turbos have to be removed,,,,so now is the the time to replace any hoses or seals when you have everything removed.
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Thank you very much. Once everything is put back together are there any specific procedures for fuel pressure / coolant bleeding that should happen before the engine is started again? Reason I ask is that you are disconnecting the fuel line and some coolant lines so wasn’t sure if you just start the engine back up or if there are some protocols to get everything pressurized and set before the engine is started.
Thanks again!
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You can cycle the key a couple of times to prime the fuel rails,,,,on the coolant just top off the coolant,leave the cap off the expansion tank and you will have to add some coolant while the engine is running,,,now the small coolant tank for the turbo you fill up and you will have to drive it around the block and recheck the coolant level,,,you may have to do that a couple time on the turbo coolant tank until it bleed the coolant.
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Thanks again! Unfortunately this is a push button start so no key.
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What is this aftermarket coolant bypass hose Tom Busey was talking about in his post dated November 30 2017?
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Tom didn’t go with a factory hose,,,he went with a aftermarket hose,,,,the by- pass hose is a 3way hose which goes to each cylinder head and sits right behind the alternator
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Who makes the aftermarket coolant bypass hose your referring to?
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I’m sure any aftermarket coolant by pass hose will work
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I’m pretty sure it is this one:
BMW Engine Coolant Hose – Rein 17127576363 but check the fitment.
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