PS: Fan Clutch.
1. Soak the Fan Clutch Nut way ahead of time: get a drinking straw and pour some PB Blaster down the straw in such a way that the penetrating oil gets to the interface of the nut and the WP shaft (a very tight space).
2. During re-installation of the Fan Clutch nut, it is very difficult to start the threads. Here is my "Poultry Cord" trick:
http://www.bimmerfest.com/forums/sho...d.php?t=240143