M54 Engine Head Casting Flaw

[lkstaack]

I have a slow oil leak in the #2 spark plug tube that is not caused by a valve cover gasket (VCG) malfunction. I haven't found anyone who has heard of such a thing; but perhaps someone here has. I captured the attached service bulletin from the other E46 forum site. It is not formatted as a BMWNA service bulletin, so it is either European or made up.

I first noted oil in my #2 spark plug tube in late 2010 as I was about to install my supercharger (42K miles on the odometer). I assumed that my VCG had failed, so I replaced it. I noticed oil in the tube again about 5k miles later. I assumed I screwed up the VCG oil tube ring installation, so I removed and reinstalled it. I discovered oil there again, so I took it to Ronin Autowerks in Orange County. They R&R both the VCG and new valve cover. That didn't work. A technician at La Jolla Independent suggested I try high-temp gasket seal in between the VCG oil tube ring. Again, no joy.

So, it seems that I do indeed have a casting flaw between the oil pressure supply passage and the spark plug tube. And, it seems that replacing the head is the only solution (unless anyone else has an idea).

I took my ZHP to the dealer when it was still under the CPO warranty. Of course, they blamed the oil leak on the supercharger and would not budge. They said that the service bulletin I had was not from BMWNA and probably bogus. They could care less if I contacted BMWNA.

The oil leak hasn't caused any performance problems, though oil will come up over the spark plug boot and drip onto my headers if I don't keep the tube drained. It is an inconvenience, but the only solution seems to be a new head....about $6k I guess.

Anyone have any thoughts?

[terraphantm]

it looks like that could have maybe come from an old version of TIS... I can't find that specific document however

[wsmeyer]

From your description it sounds like a casting defect on the gasket surface?

Any chance of getting a pic of it?

As far as it being covered under warranty, the CPO warranty is through BMW not the dealer so I would think that any dealer would be salivating at the thought of doing such an expensive repair on BMW's dime. Though your engine mods might have thrown a monkey wrench in that.

Considering the amount of miles and that you didn't mention it getting worse it sounds like it's not effecting the head in a structural way so I would try a lot of stuff before replacing the head.

[Avetiso]

Eeps, good luck with this one.

[echo46]

Very interesting. I would have been stuck on the valve cover gasket. Keep us posted on this one.

[lkstaack]

From your description it sounds like a casting defect on the gasket surface?

Any chance of getting a pic of it?

As far as it being covered under warranty, the CPO warranty is through BMW not the dealer so I would think that any dealer would be salivating at the thought of doing such an expensive repair on BMW's dime. Though your engine mods might have thrown a monkey wrench in that.

Considering the amount of miles and that you didn't mention it getting worse it sounds like it's not effecting the head in a structural way so I would try a lot of stuff before replacing the head.

I've attached pics from the OP of the E46F post. I can't see any cracks down my tube. BTW, I have tried alot of stuff. I posted here for new ideas.

I forgot to mention that I also coated the outside of the spark plug tube with JB Weld in the event oil was being introduced from top of the head.

[zhp43867]

The car being supercharged throws a monkey wrench into the whole thing... is there any way it could have been caused by that extra stress?

Keep us updated & good luck.

[lkstaack]

The car being supercharged throws a monkey wrench into the whole thing... is there any way it could have been caused by that extra stress?

Keep us updated & good luck.
Despite the fact that the spark plug tube was filled with oil prior to installing the SC, there isn't any way that cylinder pressure could affect an oil passage line outside of the cylinder. At least, not that I am aware of.

[Hermes]

A technician at La Jolla Independent suggested I try high-temp gasket seal in between the VCG oil tube ring. Again, no joy.

Did you pick Carl's brain (I'm guessing you talked to Chris or Ben)? I know he's not a fan of non-factory FI and will grumble about your supercharger, but he should be able to figure it out for you

edit: talked to Carl a little while ago, he said he doesn't recognize your car. Did you take it in for service or just talk to them?

[lkstaack]

I had the problem fixed. One month in the shop and $6,922 later. Yes, you read that right. It has been a month of frustration and disappointment, but at least my ZHP is on the road and pulling strong.

I lived with that oil leak for five years. At first, I only had to pull the #2 spark plug about every 4-5 months to drain the oil from the tube. Lately is was about every 3 weeks. If I didn't pull the plug in time, oil would drip onto my exhaust manifold and it would get smoky inside and out. I knew I had to fix it eventually; I couldn't sell it like that and it was a potential fire hazard. So, I decided to bite the bullet and get my head replaced.

A new head is expensive; about $2,500. I didn't want to pay that kind of money, particularly when heads are usually pretty robust. I considered a junkyard head or eBay for about $500, but then I found a place in Alabama that specializes in rebuilding BMW heads, Autohead Performance. They sell rebuilt heads for $800, $1,700 less than a new head. For $220 more, they'll send you a rebuild Vanos to go with it. I ordered them both and scheduled some shop time with Euro Auto Spot in San Diego.

I don't know that much about local Bimmer shops since I usually wrench my own car. However, Euroautospot did me right when my electric throttle failed due to corrosion and a partially broken connector. Most shops would have advised me to replace the entire wiring harness, but Euro Spot soldered a connector from a donor harness they had at a small fraction of the price.

Euro Auto got right on my car and quickly identified scoured journals on my exhaust camshaft and cam shelf. I was on the fence about replacing it, but Mike Miller from Bimmer and Roundel advised me to replace it. Unfortunately, there was not a single ZHP cam at any BMWNA Dealership. So, I requested and paid for "expedited service" from GetBMWParts.com (BMW of Silver Spring). Instead of getting a single cam, I ordered the ZHP "cam kit" because it was only two hundred more. The "expedited service" cost $75 was supposed to get my cams into the U.S. within five to seven working days. They came in three weeks later and two-day aired to Euro Spot.

I expected my car to be ready the next day, but got bad news instead. A camshaft shelf stud was pulling away from my new rebuilt head when torqued. Shelby from Autohead Performance told me that the studs sometimes pull if you torque it to BMW spec. He said that he always torques them to seven pounds instead of the BMW spec of 11 pounds. He recommended a time sert in the head of the lifting stud, or he would reimburse me the price of the head if I returned it. Shane, my mechanic and owner of Euro Spot, strongly advised against using a time sert in the head. His office staff found a new head for $2k. After driving rental econo-boxes for almost a month, I was ready to agree to anything. So I bit the bullet and authorized a new head.

I don't have a happy ending yet. Shane reported the next day that the rebuilt Vanos I got from Autohead was bad. It was triggering an "Inlet camshaft, stiff" fault code and the low oil pressure light was triggered at idle. Shane said he removed and installed it twice with the same result. He installed my original Vanos, and the errors never appeared. I was charged an additional $470 in labor because of the extra work.

So, I finally got my ZHP back and it runs great. I'm still breaking it in, so I haven't opened it up. I paid a total of $3,900 in parts and $3,015 in labor (I was charged an additional $714 above an beyond because of my ESS Supercharger). Did I get overcharged? Maybe. I certainly had some hard luck. I ended up paying almost half of what my car is worth. However, I'm in love with my car and I know that I could never find one to replace it for less than $50k. I plan on keeping it for years to come.

I kept my old head and worn cams. I still don't know what is wrong with the head, but I'm sure that the valves and springs are still good. Anyone need some?

[slater]

dang. that sucks. but your argument for being happy with the car now and not being able to find a replacement for less than $50K brings justification. it's only money!

i doubt your old head and worn cams are worth little more than scrap value, but you could always build a coffee table out of them. :)

what is going on with the rebuilt head from autohead performance? i would have shane @ euro spot try to help you out with returning it to autohead (along with your rebuilt VANOS unit which is clearly defective).

hope it works out!

peter