N52 valve cover

[80stech]

So I'm looking at doing the valve cover gasket on my E70 with N52, anyone done this and have some hints or advice? There is supposedly a changeup valve cover and I am pretty sure mine as been apart before but how do I tell if valve cover has been changed? what was the issue with the original? Also wondering if anyone has changed up the lifters (I have the lifter noise) and how that went? Supposedly there is a changeup head for that issue as well but I will likely live with it as is so more curious than anything

[getty150]

Originally Posted by 80stech

There is supposedly a changeup valve cover and I am pretty sure mine as been apart before but how do I tell if valve cover has been changed? what was the issue with the original?

I'm not fortunate enough to have that N52...I've got the good ole M54. No matter if it's been changed or not. Does the engine smoke? and are you topping off engine oil frequently?
From what I understand when I did my VCG is that your looking for leakage of oil! And the area is right above the exhaust manifold pipes. The oil drips on the pipes and this results in a smoking stench when the engine gets hot. As it cools the opening closes so sometimes it exposes itself long into the drive... happened to me.

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[Attacking Mid]

The N52 incorporates the ccv system into the plastic valve cover. Along with various internal passages, it incorporates a rubber diaphragm valve which provides one-way ventilation. The diaphragm will fail at some point - anything north of 100K miles and you're probably on borrowed time. There are aftermarket suppliers that will sell you a replacement diaphragm which requires chiseling off the cover and then re-adhering with acid or epoxy. FWIW, results have been mixed (at best) with these solutions.

Additionally, the internal passages can become clogged which prohibits proper function of the CCV system. There are cheaper aftermarket replacement valve covers that also have had mixed results.

When mine failed, I first tried replacing the diaphragm. While it sortof worked, I believe I also had some internal clogging. After a few months, I finally got frustrated and bought a new BMW VC. No problems since.

I haven't explored the aftermarket offerings lately, so perhaps there are better options available now, but as of a few years ago, many of us ultimately ended up buying BMW VC's.

AM.

[80stech]

OK thanks! I'll take it apart and see how it all looks. As far as I can tell, the updated valve cover uses 1 less hose for the CCV, What's on the car now doesn't have a hose hooked up to the plastic covered pot thingy at the back and there seems to be a slotted cap on it maybe making it into a vent, maybe the changed up system is an actual PCV system and not closed? The change up valve cover kit with the updated heated elbow etc. doesn't seem to be available anymore so if I do need a valve cover I think I'll have to go with the Elring one.

[80stech]

@Atacking Mid - When you say "no more problems" and "mixed results" what kind of problems are you talking about ?vacuum leaks/mixture codes/driveability, oil leakage or all of the above? Does the upgraded BMW valve cover have a slotted cap on the fitting of the pot thingy that I assume was the vacuum reg. for the original system?

[Attacking Mid]

When I replaced the diaphragm, I solved the immediate problem of the huge vacuum leak and whistling caused by the failed diaphragm. However, the vehicle never idled right, which I believe was caused by excessive vacuum due to clogging in some of the VC's internal passages. Once I replaced it with a BMW cover (not updated AFAIK), I've had no problems since with either the CCV system or with oil leaks.

BTW, that nipple on the housing for the diaphragm is not supposed to have a hose. It's simply an atmospheric vent for the diaphragm.

I said results had been mixed for both the diaphragm replacement and for aftermarket VC's based on my observations of perusing various BMW forums over the years. Some have reported success, while others (like) me have reported no success with either diaphragms or complete aftermarket VC's.

I'm not aware of this updated cover you've mentioned, so I can't comment. Hopefully they've made some improvements, as it is somewhat unacceptable in my mind to have to replace a $500 VC every 100K or so.

AM.

[andrewwynn]

That's fantastic feedback from [mention]Attacking Mid [/mention] !

I'm about to change my VC which has been leaking at the gasket so it's been on the next on the list and suddenly it also has an internal vacuum leak so I'm about to order an OEM from FCP. Annoyed that the OEM is not made in Europe but can't convince myself to spend over twice the price since either comes with the same warranty.

As mentioned follow the torque pattern and values when installing!

If n52 has grommets like the m62 I'd get new ones. The N55 I have uses self tapping screws to hold the seal for the Valvetronic so TIS calls for fresh ones.

[80stech]

Now that I think of it, when I checked into this a while back it seems to me that the update includes removing the cyclone assembly under the intake which is why there is one less hose. Yes, I've done a bit more checking and you are right that nipple is and was originally a vent (for the diaphragm not the crankcase) so I wonder if there even was any changes made to the valve cover? Back at that time I was going to remove the intake and walnut blast but using premium gas (prev owner was likely using reg) has cured most of the stumble and idle problems. Things aren't cut and dry as far as the update for the heated vent elbow either so I will probably just do the valve cover for now and maybe first take out the valvetronic motor and see if most of the leak isn't from there.

[Attacking Mid]

One would hope that Elring wouldn't put their name on the aftermarket VC unless they were confident in the supplier's design and manufacturing. When I was dealing with mine, the only choices were genuine BMW and no-name Ebay/Amazon Chinese covers. I read several reports of people having trouble with those covers at the time, so I bought a genuine BMW. I'd probably try the Elring today with FCP's warranty backing it up. The only downside is the VC is not a trivial job to replace, though the cost difference would be worth the risk to me.

AM.

[andrewwynn]

I came to exactly that conclusion.

We have two N55 in the family one with 170k one with about 70k so I'm the test bed for how to fix


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