belt tensioner problem
 

I'm trying to replace my '01's alternator. I can't release the tension on the belts. I push down on the idler pulley and nothing happens other than the 24mm bolt head turning.
I turned the bolt quite a few turns; will the bolt finally shear or will turning it too much cause the pulley to bind? A youtube video made it look ridiculously easy but...
TIA!

Are you pushing down on the wrong bolt?
http://serpentinebelthq.com/wp-content/uploads/2012/12/2000-Porsche-Boxster.jpg

There is a nut on the back side, 15mm I think, so the whole thing may be turning. Sounds like you have to tighten the bolt up a bit to get it to loosen the spring. Slip the 15mm open end on the back side and tighten the 24 up.

Take a picture of how the belt runs because it will give you a stroke trying to remember how it goes.

I had the correct bolt. The nut on the rear was spinning. Thanks!!