BMW Repair: Alternator, tensioner pulley, hex head

Question
Hey Evan
I am trying to replace the alternator in my '97 528.  I can not figure out how to remove the drive belt.  I see the pulley that relieves the tension but I do not see how to move it.  I took the cap off of the pull thinking something there but I still am not figuring it out.  What am I missing?
Thanks for the help.

Answer
Nick, Use the T-50 screw or allen head screw (depending on version) that is in the center of the tensioner pulley. Also the tensioner pulley will sometimes have a 17mm hex head cast into the body of the tensioner. Turn clockwise to release belt. Note belt routing before removing. Will need to remove the idler pulley on top before removing alternator. When you remove positive battery cable wrap metal end with masking tape to avoid the cable arcing on other metal components.
-Evan