Vanos bolt failure (pictures)

[wolfe]

Took some pictures of the failed vanos bolts on my n52, for anyone interested in what is affected by the vanos bolt recall campaign.

Symptoms started with occasional stalling, then 2A87 exhaust vanos fault codes.

When I removed the valve cover, I could see two of the exhaust vanos adjuster unit bolts had backed out several turns. One was still seated properly, and the fourth bolt head had snapped off.

The intake vanos unit bolts were all still seated correctly.

I replaced both units with the updated parts - notably the new units came with black bolts vs. the silver bolts that failed.

Here's a couple of pictures of what the failure looks like:

failed exhaust adjuster unit:


new unit with updated bolts:

[MotoWPK]

Do you know at what point in time a change was made to the VANOS bolts in N52 production to use these black bolts?

And, what do you about the broken off bolt head - were you able to recover it or is it lost in the sump?

[wolfe]

I don't know when the production date change happened unfortunately. The tech bulletin I could find online mentions up to November 2011 production dates: https://static.nhtsa.gov/odi/rcl/201...4V176-2716.pdf

I definitely plan to recover the broken bolt head if I can - without knowing how long ago it broke, it's possible that it's already come out during an oil change. I've looked all around the valve train and timing chain gear with a borescope, flashlight, and mirrors and am pretty confident that it's either in the sump or has come out already.

[E91WAG3N]

Wow. How many miles on your motor?

[Craig in Alabam]

Hi Folks,

I was talking to my SA today about getting the airbag recall done (my airbag is finally here!) and I asked him about the VANOS recall. He said that it is a service related issue. That is, if you are having issues with the car and it turns out to be the VANOS bolts, BMW will make the repairs for free. The warranty for this issue has been extended to 10 years (unlimited mileage). But they won't just fix it if there's no problem.

I went to this page:
http://www.bmw-rp.com/production/isg...nsf/submit.xsp

and it shows the VANOS recall and the FRM recall in the drop down menu. Apparently you can get reimbursed, maybe? My FRM has already been replaced.

On a side note, the name and address that came up on this page were for the previous owner of my car. Hmmm...

Anyway, sorry if this is old news.

Cheers!
Craig

[wolfe]

Originally Posted by ubersteuer

Wow. How many miles on your motor?

75k miles.

And yes, sorry I didn't make that clear - this is absolutely covered by the recall so no need to spend out of pocket. I had the valve cover off anyway so figured I'd just do it myself rather than put everything back together and have the dealer take it all apart again in a week.

[juld0zer]

The bolt heads end up in the sump, sometimes in the oil pickup snorkel too

[wolfe]

Originally Posted by juld0zer

The bolt heads end up in the sump, sometimes in the oil pickup snorkel too

Thank you. Do you think I have any hope of getting them through the oil level sensor hole or oil drain hole with a borescope as opposed to dropping the sump?

[juld0zer]

Possible - it is worth a try! Also look carefully around the head

[chris_flies]

When I'm driving up a slow hill in 4th gear, and then I go to the gas to keep up my speed, I hear a sort of crunch/clunk when I push the gas to a certain point. Also, my engine will sorta chug, or shudder if you don't get on the gas soon enough when releasing the clutch from a stop. The car doesn't show any codes (except TPMS codes, because $200, when I can just look around the car is dumb), could these symptoms be indicative of something such as the VANOS solenoids being clogged/going-bad, or possibly something in the Valvetronic system? Any help is appreciated.

[five_timer]

Thought I'd share my unfortunate experience, which unexpectedly yielded awesome results.

It started back when my nephew - who's a mechanic - was servicing my car. With 120k miles on the engine, the car was leaking oil. He gave me the bad news: I needed to replace my valve cover gasket, my filter housing gasket, and my oil pan gasket. Plus, my pan looked like it was rusting through. It would be both big labor and cost to do all the work, but as long as I kept an eye on the oil level, I could get the work done a little bit at a time.

So fast-forward to some time later, when I still haven't had any of the work done yet. I'm driving home from work, noticing that my average MPG reading has been strangely dropping. Now I start displaying my instant MPG, and it's way below normal, so I know something's wrong, but my oil level is OK.

When I get off the highway, I come to an intersection near my house, and it sounds like the car in front of me (some compact car) has a diesel engine. When that car goes through the intersection, I realize it's my engine!

After a video diagnosis, a flatbed tow, a diagnostic, and some online research, it seems like the Vanos bolts came loose, which is covered by a 10 year (no limit) extended warranty. It's also been recalled, so now I have it towed (once again) to my BMW dealership.

BMW claims my N52 engine, built in December of 2010, is not part of the recall, even though the service notice clearly includes it. Anyway, the service manager says that the extended warranty would cover all work to replace the Vanos unit; including fishing out the bolts from my engine! In order to do that, they had to open up - and then replace - my valve cover gasket and my oil pan gasket. They could also determine that my oil pan was fine, and was not about to rust-through.

The warranty covered about $3k worth of work, of which nearly $2k would've been required for my oil leak repairs. Is that turning a lemon into lemonade, or what?