X5 3.0 Alternator and belts DIY (with pictures!)

[generx]

Just came across this, glad this was helpful to everybody. This entire site has been a tremendously helpful resource for me as well and I'm just happy that I was able to contribute in a small way.

[dandog96]

More thanks for the help. Sorry to bump an old thread, but I can't seem to get my serpentine belt on. I have tried countless times and it is just barely too tight to install, even after easing tension. Any advice? I feel as though my idler pulley and tensioner pulley are very close and this worries me a little....

[dandog96]

Its the old belt. I had to swap alternators. I took the diagram from an e46 with the 3.0. I think I might have to find another wrench thats longer so I can apply more torque. Is it necessary to remove the fan? Also are the idle pulley and tensioner supposed to be so close when the belt is not on?

Thanks for the help

Originally Posted by trader4

Unstated is whether it's a new
belt, were any components changed, etc.
Are you sure you have a clear diagram of the proper belt routing:

M52 Belt Routing Photo by deathwarden5 | Photobucket

The pic in the lower left shows it as well as the normal spacing of
tensioner and idler pulley. You have to put a lot of force on the
tensioner to move it over. With it all the way over, the belt should
just slip on, I've never had an issue.

[cn90]

I recently did my CCV and OFH, in the process of doing these 2 tandem jobs, I removed the alternator.
All the tricks are listed in the thread below.

You can disconnect the battery cable in the trunk if you wish. I didn't.

http://www.xoutpost.com/bmw-sav-foru...-overhaul.html

PS: Stick to Valeo or Bosch, brand-new if you can. Rebuilt alternators are hit and miss these days!!!

[dandog96]

Thanks for the link that looks helpful. Just wondering, I have a bit of oil around my alternator and quite a bit on the idler pulley for some reason. Is this cause for worry? The engine runs perfectly fine but I do not want to take any chances...

Originally Posted by cn90

I recently did my CCV and OFH, in the process of doing these 2 tandem jobs, I removed the alternator.
All the tricks are listed in the thread below.

You can disconnect the battery cable in the trunk if you wish. I didn't.

http://www.xoutpost.com/bmw-sav-foru...-overhaul.html

PS: Stick to Valeo or Bosch, brand-new if you can. Rebuilt alternators are hit and miss these days!!!

[crystalworks]

Originally Posted by dandog96

Thanks for the link that looks helpful. Just wondering, I have a bit of oil around my alternator and quite a bit on the idler pulley for some reason. Is this cause for worry? The engine runs perfectly fine but I do not want to take any chances...

Those leaks are either going to be your vanos oil supply hose with the banjo fitting... or your oil filter housing. If it is ALOT of oil it can shorten the life of your alternator... but if not it's more of an annoyance. The vanos oil supply hose is an easy fix so I'd probably hope it was that. Oil filter housing gasket is also fairly easy, but time consuming.

[cn90]

@dandog,

Oil on alternator is from PS Reservoir return hose.
Basically, cut off 1/2-inch of the hose and re-attach.
If you quickly cover the PS Reservoir bottom port, then you don't need to add PS Fluid.
But check PS Fluid anyway.

See Step #19 in the link below:

ENTIRE COOLING SYSTEM REPLACEMENT Tips and Tricks (Very Long, Enjoy!)

[crystalworks]

^He said oil. I was assuming he had ruled out that it was not ATF. If it IS in fact ATF, then yes, it will be what cn90 said.

[dandog96]

Small update. I finally installed the serpentine belt. Not sure if my method was technically correct but it worked. I took off the idler pulley so it didn't interfere with the belt and then installed the belt on the rest of the areas. Then I released tension and put the idler pulley back on.

On another note, I heard that it is often the voltage regulators that go bad in these alternators. B/c of this I removed mine and saw that it was full of gunk where the rotor meets the brushes of the regulator. I cleaned it out and took it to auto zone where they tested it and it passed. I then installed it in my car and it worked for a couple of days... Fast forward to today when I am having the battery light and low voltage again.

Here is what I am wondering:
Is the alternator bad?
Could it be some kind of drain caused by faulty wiring that is causing the battery to die?


Once again, sorry for dropping all these questions but I am at my wits end.

[cn90]

You have 2 options:

1. Replace only the VR. About $50 or so.
If you choose this route, then make sure you buy the correct VR (Bosch vs Valeo).

Valeo info below:

Diy: Valeo alternator rebuild - Bimmerfest - BMW Forums


2. Brand-new Alternator is Bosch AL0703N (don't buy the AL0703X, as "X" stands for rebuilt with questionable quality these days). New is better.
About $235 at eeuroparts dot com, ebay etc.
Valeo and Bosch is interchangeable.