[E9Slow]

Well, it looks like I'll be adding myself to the extensive list of members who are in need of a young valve cover replacement. My 07 e90 328xi has 83k, and lately, I've noticed some obvious signs of a leak (typical wetness around mating surfaces and the buildup of crud) but lately it's gotten prominently worse, to the point now at times I can faintly smell burning oil while driving when at a stop, and much more saturation around the mating side, especially on the passenger side, to the point now I can see where it's been dripping onto the wire of the o2 sensor, down the cats, and even a little bit on that low motor mount (believe that's what it is down low on pass. side). Well tonight, going to pickup dinner, I rounded a rotary, admittedly with a bit of speed as I was playing with the DS mode on my auto (quite fun with a muffler delete, btw!) and I had to hold a hard left going around the rotary, so the body roll was all on the passenger side, and very shortly after I arrived at the pizza place, and when I parked, I noticed some smoke coming from under the hood. I hopped out, popped the hood, and saw it was clearing coming from the mating surface, right near where it leaks over the o2 wire, and was dripping onto the cats, making prominent smoke. It slowed down quickly once the car was still, and the smoke faded after the drip stopped, but its become clear this VCG must be very due at this point. That being said, I'll probably be taking this on for my Memorial weekend project. Here's some pics:


Notice how heavy the seepage is near that 2 bolt flange-looking part nearest the now-wet o2 wire:






If for any reason anyone thinks this is something different, or has anything to add on the issue, please chime in!

Also, anything special to take note of while doing the valve cover job? I already checked, and I have the bolts that are reusable, although I may order new ones anyways. Is there anything else necessary or strongly recommended to replace at the same time while I'm in there? Always open to suggestions and advice from those who've "been there, done that".

[seccsc]

Originally Posted by E9Slow

Well, it looks like I'll be adding myself to the extensive list of members who are in need of a young valve cover replacement. My 07 e90 328xi has 83k, and lately, I've noticed some obvious signs of a leak (typical wetness around mating surfaces and the buildup of crud) but lately it's gotten prominently worse, to the point now at times I can faintly smell burning oil while driving when at a stop, and much more saturation around the mating side, especially on the passenger side, to the point now I can see where it's been dripping onto the wire of the o2 sensor, down the cats, and even a little bit on that low motor mount (believe that's what it is down low on pass. side). Well tonight, going to pickup dinner, I rounded a rotary, admittedly with a bit of speed as I was playing with the DS mode on my auto (quite fun with a muffler delete, btw!) and I had to hold a hard left going around the rotary, so the body roll was all on the passenger side, and very shortly after I arrived at the pizza place, and when I parked, I noticed some smoke coming from under the hood. I hopped out, popped the hood, and saw it was clearing coming from the mating surface, right near where it leaks over the o2 wire, and was dripping onto the cats, making prominent smoke. It slowed down quickly once the car was still, and the smoke faded after the drip stopped, but its become clear this VCG must be very due at this point. That being said, I'll probably be taking this on for my Memorial weekend project. Here's some pics:


Notice how heavy the seepage is near that 2 bolt flange-looking part nearest the now-wet o2 wire:






If for any reason anyone thinks this is something different, or has anything to add on the issue, please chime in!

Also, anything special to take note of while doing the valve cover job? I already checked, and I have the bolts that are reusable, although I may order new ones anyways. Is there anything else necessary or strongly recommended to replace at the same time while I'm in there? Always open to suggestions and advice from those who've "been there, done that".

Be careful when using a flat tool to pry the VCG from the engine. The gasket sets in a groove and broke off the inner groove in a couple spots pushing in with a flat tool. I had to retrieve those small pieces in the valve spring region.
Removing all of the interference for VCG is 3 hours.
Good luck!

[E9Slow]

Originally Posted by seccsc

Be careful when using a flat tool to pry the VCG from the engine. The gasket sets in a groove and broke off the inner groove in a couple spots pushing in with a flat tool. I had to retrieve those small pieces in the valve spring region.
Removing all of the interference for VCG is 3 hours.
Good luck!

Thanks, I'm definitely going to make a day of this, I want to go slow and cautious, and I plan to clean and degrease any and every part I remove while I'm at it, to A) ensure a clean mating surface all over and maintain engine cleanliness and B) to help identify future problems or leaks in case anything else is leaking too.

[V-Viper]

80k actually seems pretty old for a VC to start leaking :O Usually get one at least every 50k!

[Needbmwpartzz]

I'm shocked to hear vcg possibly even leaking at that low mileage
I'm way over 100k and no leaks yet....knocks on wood!

[E9Slow]

Originally Posted by Needbmwpartzz

I'm shocked to hear vcg possibly even leaking at that low mileage
I'm way over 100k and no leaks yet....knocks on wood!

I'd love to know what kind of conditional factors cause these failures. From my searching here and other forums, it definitely seems this is a wildly varying problem, with some running into it as early as only 20k miles, and stretched as far as over 150k and still never having had it replaced yet! I don't know if maybe BMW used different types/qualities/brands throughout different models of the N52 and some were better than others, or if it's purely coincidental; it either survives or doesn't. Regardless, it certainly seems to be a very common issue, along with the short-lived electric water pumps. I know all cars have their flaws and "common problems" over years and models, but it seems frequent enough that BMW should warrant replacements of these VCG. The parts really aren't overly expensive, so it wouldn't be a huge deficit for them in exchange for keeping owners happy and proud of BMW. I guess that's another conversation for another time though.

Drove it some today, and it seems like the drip & smoke is fairly random, and happens about once shortly after start-up, then stays fine for the remainder of the ride. I got up to grab my coffee, not far from home, and it did it once in the drive through (a few plumes of white smoke and oil smell for a few minutes) and then never did it again while I drove about 15mins across town. After leaving the store I had gone to, maybe 3-5mins into the ride, it did it once more (this time though I had the windows up and the smell came into the cabin through the vents, which was pretty overwhelming, had to put all the windows down) and then was fine again the 20min ride home.

On a side note, is this doing any severe harm to the engine at all? I'm taking it easy on the car in the mean time until I get the new gasket installed (probably next/memorial day weekend when I'm off for a few days) and I can't imagine any serious harm is being done, the drip is no better or worse than when it first began, and it's condensed to just one drip point which lands right on the upper catalytic converter, and burns off immediately. When cold, it hardly drips at all, and only lands on that lowest motor mount. Think I'm ok for a few more days? After the job is done, I'll also complete a fresh oil change too.

P.S.- One thing I've wondered, is I believe the previous oil changes were usually Castrol Euro Blend 5w30, and recently we had a sale at work on Mobil1, so I grabbed some Mobil1 Euro 0w40 for the change this time, as I've read either or are perfectly fine for the N52 as a substitute for OEM BMW oil. I'm wondering now though, is it possible the thinner 0w40 was just more susceptible to leaking more through the tired VCG than the thicker 5w30 was? If that's so, maybe I should just go back to the 5w30 and stick with that. I do live in CT where this years winters temps saw as low as ~-10*F to now in the warmer months to ~70-90*F.

As always, thanks guys!

[cybermgm23]

Originally Posted by E9Slow

I'd love to know what kind of conditional factors cause these failures. From my searching here and other forums, it definitely seems this is a wildly varying problem, with some running into it as early as only 20k miles, and stretched as far as over 150k and still never having had it replaced yet! I don't know if maybe BMW used different types/qualities/brands throughout different models of the N52 and some were better than others, or if it's purely coincidental; it either survives or doesn't. Regardless, it certainly seems to be a very common issue, along with the short-lived electric water pumps. I know all cars have their flaws and "common problems" over years and models, but it seems frequent enough that BMW should warrant replacements of these VCG. The parts really aren't overly expensive, so it wouldn't be a huge deficit for them in exchange for keeping owners happy and proud of BMW. I guess that's another conversation for another time though.

Drove it some today, and it seems like the drip & smoke is fairly random, and happens about once shortly after start-up, then stays fine for the remainder of the ride. I got up to grab my coffee, not far from home, and it did it once in the drive through (a few plumes of white smoke and oil smell for a few minutes) and then never did it again while I drove about 15mins across town. After leaving the store I had gone to, maybe 3-5mins into the ride, it did it once more (this time though I had the windows up and the smell came into the cabin through the vents, which was pretty overwhelming, had to put all the windows down) and then was fine again the 20min ride home.

On a side note, is this doing any severe harm to the engine at all? I'm taking it easy on the car in the mean time until I get the new gasket installed (probably next/memorial day weekend when I'm off for a few days) and I can't imagine any serious harm is being done, the drip is no better or worse than when it first began, and it's condensed to just one drip point which lands right on the upper catalytic converter, and burns off immediately. When cold, it hardly drips at all, and only lands on that lowest motor mount. Think I'm ok for a few more days? After the job is done, I'll also complete a fresh oil change too.

P.S.- One thing I've wondered, is I believe the previous oil changes were usually Castrol Euro Blend 5w30, and recently we had a sale at work on Mobil1, so I grabbed some Mobil1 Euro 0w40 for the change this time, as I've read either or are perfectly fine for the N52 as a substitute for OEM BMW oil. I'm wondering now though, is it possible the thinner 0w40 was just more susceptible to leaking more through the tired VCG than the thicker 5w30 was? If that's so, maybe I should just go back to the 5w30 and stick with that. I do live in CT where this years winters temps saw as low as ~-10*F to now in the warmer months to ~70-90*F.

As always, thanks guys!

You're valve cover itself may also be cracked. I recently took my 2011 328i to the dealer for an oil change (76K mi) and they told me that the VCG had failed and the VC itself was cracked. They also replaced the oil pan gasket and the OFHG as well. All under extended warranty. It seems that BMW gaskets don't hold up long and the VC is made of hardened plastic....on a $47K vehicle no less.....

[E9Slow]

Originally Posted by cybermgm23

You're valve cover itself may also be cracked. I recently took my 2011 328i to the dealer for an oil change (76K mi) and they told me that the VCG had failed and the VC itself was cracked. They also replaced the oil pan gasket and the OFHG as well. All under extended warranty. It seems that BMW gaskets don't hold up long and the VC is made of hardened plastic....on a $47K vehicle no less.....

Yeah that's my larger concern for sure, that's not really in the budget right now after all I've spent so far on other things, but if it has to be done... I'm definitely going to go over it thoroughly, I hope the cracks will be obvious so I don't accidentally miss them and end up having to do the job twice...

I don't know who thought it would be brilliant to change to a hard plastic valve cover setup (as I see older models and some still have the metal/aluminum ones sometimes). My biggest frustration is how well known and common this issue is, but it's only taken care of under warranty. That's the biggest downside to this car, buying it from a private dealer with their minimal warranty (which has long since expired) even with my relatively low miles for an '07 (83k). So basically, unless it becomes a recall, I'm SOL. However for what we paid for this car, I suppose we can't really complain; we basically stole it (dealer was a friend).

[bartbes]

I think you should get a new valve cover use liquid sealant all over the new gasket and get a new oil cap and flapper valve/hose.

I've been in there 4 times and this is what i did to finaly solve the issue..

2007 85k

Good luck

[kkasson]

Originally Posted by E9Slow

Yeah that's my larger concern for sure, that's not really in the budget right now after all I've spent so far on other things, but if it has to be done... I'm definitely going to go over it thoroughly, I hope the cracks will be obvious so I don't accidentally miss them and end up having to do the job twice...

I don't know who thought it would be brilliant to change to a hard plastic valve cover setup (as I see older models and some still have the metal/aluminum ones sometimes). My biggest frustration is how well known and common this issue is, but it's only taken care of under warranty. That's the biggest downside to this car, buying it from a private dealer with their minimal warranty (which has long since expired) even with my relatively low miles for an '07 (83k). So basically, unless it becomes a recall, I'm SOL. However for what we paid for this car, I suppose we can't really complain; we basically stole it (dealer was a friend).

BMW change the material of their valve cover gaskets a few years ago, the new gaskets are much more resistant to synthetic oil. They last a long longer, from what I can tell.

If you find a crack in the valve cover you can sometimes epoxy it shut. Just be sure not to disrupt the mating surface of the gasket.

Also FYI the flange that it looks like it's leaking from is where the secondary air pump would attach to the exhaust if it were an N51. N52s just have that cover instead of the air pump, but it just goes to the exhaust. So there's no chance of the oil coming from there, just the valve cover.

[E9Slow]

Originally Posted by kkasson

BMW change the material of their valve cover gaskets a few years ago, the new gaskets are much more resistant to synthetic oil. They last a long longer, from what I can tell.

If you find a crack in the valve cover you can sometimes epoxy it shut. Just be sure not to disrupt the mating surface of the gasket.

Also FYI the flange that it looks like it's leaking from is where the secondary air pump would attach to the exhaust if it were an N51. N52s just have that cover instead of the air pump, but it just goes to the exhaust. So there's no chance of the oil coming from there, just the valve cover.

Trial and error I guess there... Definitely an error with the OEM original gasket material.

Thanks for the info, that's good to know, if I find and minor cracks, I might try that route first. What have you used, just JB weld or similar?

And thanks, good to know about air injection pump. For now I'm not too concerned because the leak is very mild and I haven't seen or smelt anything since the last time I posted, just driving a little easier in the meantime.

[PhaseP]

If you are planning to keep the car for a while, I suggest bite the cost and buy a new valve cover. Besides being prone for cracking, the Crank Case breather valve is part of the valve cover, and it also ages and can start to give trouble. It is not a serviceable item. I believe new valve cover comes with new gasket(s), but you should double check. So that may offset the cost.

Also if you are going to reuse the existing valve cover, it is good time to replace the eccentric shaft sensor gasket (the small round one towards the front of the cover that a cable gets attached), and the valvetronic motor gasket. I think new valve cover comes with those too, but again you should check.

[E9Slow]

Originally Posted by PhaseP

If you are planning to keep the car for a while, I suggest bite the cost and buy a new valve cover. Besides being prone for cracking, the Crank Case breather valve is part of the valve cover, and it also ages and can start to give trouble. It is not a serviceable item. I believe new valve cover comes with new gasket(s), but you should double check. So that may offset the cost.

Also if you are going to reuse the existing valve cover, it is good time to replace the eccentric shaft sensor gasket (the small round one towards the front of the cover that a cable gets attached), and the valvetronic motor gasket. I think new valve cover comes with those too, but again you should check.

Hmm, that is a good point, forgot about the ccv being in there too...

Plans were to buy the gasket "kit" from ecs, which shows to include all the gaskets including the solenoids to handle everything in one shot.

[PhaseP]

Originally Posted by E9Slow

I don't know who thought it would be brilliant to change to a hard plastic valve cover setup (as I see older models and some still have the metal/aluminum ones sometimes).

First year '06 n52 models have metal (magnesium alloy) covers. I also used to think why did they change to plastic, especially seeing the plastic cover is same price as the metal one.
But my view on that changed when I had to replace the crank case breather valve (a.k.a oil separator) recently on mine. The models with metal cover have this unit outside under the intake manifold, but plastic valve cover models have it built on to the valve cover. So for price was comparison, the price of this unit and the associated extra hoses needs to be added to metal valve cover price for fair comparison.
But more importantly, it is a pain to get to and disconnect this crank case breather valve under the intake manifold where it is.

So plastic valve design makes it more simple and ends with less parts overall. Any work that involves removal of intake manifold, like starter replacement, crankshaft sensor replacement, knock sensor replacement becomes easier with the plastic valve cover versions due to this.
Even oil pan gasket replacement is easier because plastic valve cover models have the oil return from this unit inside them, where as metal valve cover models have an outside oil return line to the oil pan, which is not very easy to disconnect.

[E9Slow]

Hmm, that's actually pretty interesting. Maybe I can deal with the plastic setup after all.

Well for now, I think the plan is going to be to just replace all the top gaskets from ECS, VCG, eccentric and valvetronic motor gaskets, and while I've got that much apart, I'm also going to replace OFHG as well. I'm going to thoroughly clean and degrease the plastic valve cover, and inspect (and if necessary repair) any cracks. Reseal everything and then degrease the engine block and bay while everything is fresh and cool. Then fire it up and ensure all is well.

Side note, when replacing the OFHG, how much coolant should I expect to lose? It's going to get a complete flush when the pump & tstat get changed, so for now I'm just going to replace what I lose and then bleed it.

[tlow98]

You will only lose a few cups of coolant if the motor is cold.

Also, I'd hold off on the eccentric/valvetronic gaskets if it were me. If it ain't broke...

OFHG is pretty easy tho. Sang the snap-on 1/4" knuckle joint and soooo easy.

[E9Slow]

Originally Posted by tlow98

You will only lose a few cups of coolant if the motor is cold.

Also, I'd hold off on the eccentric/valvetronic gaskets if it were me. If it ain't broke...

OFHG is pretty easy tho. Sang the snap-on 1/4" knuckle joint and soooo easy.

Good to know, I've got a spare gallon on hand.

It seems like everyone leans toward recommending to replace both at the same time. Plus I'm also suspicious that my valvetronic gasket is leaking because I see oil leaking down from top of valve cover in center where it's located. Then the eccentric you only know if that's bad when you unplug it so I'd rather be prepared.

Thanks for the OFHG tip too, I do have a 1/4" knuckle so I'll have that ready.