Good morning fellow X3'ers. I just finished the VC gasket replacement on my daughters '07 X3 3.0si (N52B30O1). Lots of good info & write-ups on this procedure if any care to do the job. I wanted to post what I found would be helpful to others that want to do this repair them selves.
Our X3 is new to us but is what I call a high mileage car with 133k on it when we bought it. It was a BMW CPO car, so I had all the records that from BMW. I got it a good price, so felt I could fix the leaks & change all the fluids to my daughter would have a car to drive back & forth to our local college. One point to make, IF you X3 has a black plastic valve cover, you do NOT need to replace the screws. The earlier engines that have a aluminum/magnesium VC use aluminum mounting screws & are a one time use. You will need a good set of TORX sockets and will need a short small one to remove the bottom screw for the valvetronic motor. One of the hardest items to remove was the oil separator hose at the back of the VC. hard to reach & very difficult to "squeeze" to get it to release. Be careful removing this or you'll have to buy a new one if you break it.
Here is a very good YouTube video that I used. Let me know if you have any questions. Oh, I also replaced the Valvetronic motor seal & the cam location sensor gaskets. ALL gaskets were HARD as a rock. After so many heat cycle, they become very hard & brittle. That's why they leak. Here's a link to the YouTube video as the embedded isn't showing up when I preview this post.
http://youtu.be/tdtnG1kqtjo