bimmerZ

I am going to be working on my 2008 550i w/ M Sport. I am getting ready to tackle valve cover gaskets, upper timing cover gaskets, vanos o-rings, injector lower o-rings, spark plugs, and vacuum pump gasket (both). My question is this... I am fairly comfortable with all of the above jobs thanks to some awesome write-ups from other members. I need to do the alternator bracket gasket and from what I have heard, this is an absolute bear!! I haven't found any decent write ups with pics to really show why its so much of a pain in the a$$. Can anyone point me to an existing thread or share a write up they have acquired relating to the alternator bracket gasket on the 550i? Saw one write up on the N62 from a 7 series, but the layout in the engine bay looked different. Thanks in advance for any help!!

-Mike Z.

CVTBenhogan

Good luck on the jobs!! I need to do the same and haven't seen an alternator bracket DIY. Are you sure alt bracket needs to be done?

bimmerZ

Honestly, I am not 100% sure... I had the car at the stealer to scan a code that I couldn't get to come up on my scanner, which ultimately had to do with a short in my instrument cluster. I sent the cluster to BBA Reman for repair instead of paying the crazy price for a new one plus re-coded. While it was there for service, the dealer told me that the alternator bracket was leaking and needed to be replaced. I plan to double check that once I get the cooling fan and oil cooler removed to do the vacuum pump and VCG, but just from looking, I can see a small pool of oil below the alternator on the belly pan. I want to be prepared since the gasket is only $7 and the engine bay will be half torn apart anyway. There is a good DIY on pelicanparts.com in the tech section, but relates to the 7 series. Mostly the same, I think...

dingolfing

I just did this repair earlier this year on my 2008 550i and can offer assistance. The pelican parts DIY is pretty good at providing a general idea on how to tackle the job. The reason it takes so long is because so many parts in hard to reach places have to be removed. You will need the proper tools and inventive ways to get to most of the fasteners.

To accurately diagnose that your alternator bracket is bad, which it most likely is because all of your rubber on the car is failing at this exact point in life, visually inspect the bottom of the engine bay. Use this pelicanparts image as a guide:
http://www.pelicanparts.com/techarti...mall/pic25.jpg

What you are specifically looking for is that telltale brown oil drip that is forming on the bottom of the metal bracket in the center of the photo. You need to first run the engine on cold startup so the oil drip can form. A hot engine won't leak and won't show you any drip. The oil drip will look exactly like in the photo, as it did on mine, and you can even see where it starts from the crevice in between the block and the bracket.

dingolfing

Also, do the driver side upper timing cover gasket at the same time while doing the alternator bracket gasket. You will save alot of time.

bimmerZ

Thanks a lot dingofling! Are there any special tools that you needed other than the normal sockets, extensions, and a u joint extension? I plan on starting the disassembly tonight with hopes of finishing all day tomorrow. I appreciate the heads up on the timing cover also. The reason I am trying to get the alternator bracket done immediately is that I had already planned on doing the VCG, vanos seals, upper timing cover, spark plugs and vacuum pump this weekend and I would hate to put all that back together and then do the alternator at a separate time.

Also, I have the oil cooler in my 550, did you have to take the cooler and fan out to do the work or just remove the cooler lines from the bracket?

dingolfing

All sizes of extensions, up to and including the long 12" extension. Universal joints are a must. E-sockets are required for the timing covers and engine mount on the alternator bracket. As for hex (allen) wrenches, the best ones to use in this case are the single L-shaped hex keys. You'll see why when the very small clearances down there won't allow you to use anything else, including hex bits on a ratchet. Another jack is required to lift the engine under the oil pan (using a wood block).

If you plan to do all that this weekend, unless you have a friend to help you out, you won't get it done. At best, you would need a full 3-day weekend as the alternator bracket can take over 10-12 hours on its own, that's why BMW charges over 4 figures to replace that part.

Oil cooler radiator is embedded within the fan housing, so both will have to come out to give you more room to relocate the alternator. I left the alternator wiring connected along with steering pump connected and just moved them into the free opening left by the fan. Saves you from having to drain the steering pump. The cooler lines have to be disconnected from both ends, and alot of oil will drain out from the radiator outlet.

CVTBenhogan

Thanks the info. Sounds like doing the water pump makes sense while at this. I replaced my fan and had to deal with oil lines in the fan shroud. Took 3 hours. Really wished I did the water pump then.

dingolfing

Water pump can be removed without removing the fan assembly. It takes a little longer, but saves you the hassle of pulling the shroud and disconnecting the oil cooler and draining that oil.

jfife83

Go to e60 section on bimmerfest for a good diy on alt bracket gasket. ...it's not all that bad...did my 545i in half a day and a friends the second time in less than that