I have been have a screeching noise coming from the engine compartment in the recent couple of weeks. I figured that the noise was due to some pulley or tensioner for the drive belt (serpentine). I was hoping that it would die a slow death but it started to die sooner than I hoped. You can see the bearing is coming apart.
VW says to use a special pin tool to hold the tensioner in a compressed position, however you only need a bolt. The bolt must fit through hole of the hex molded into the body of the spring while turning it clockwise with a wrench to fit the bolt or pin into that is molded in the body to the right of the hex. You can see this in this picture.
To remove the tensioner from the engine, it is easier from the bottom. At least it was for me. Also you can see that there is a hex socket bolt that it is mounted with to the engine. Just the one bolt holds it.
Here is the new part compared to the old. I bought Gates brand for both parts. The tensioner was made in Germany but the belt was made in the USA. The interesting thing is the new tensioner is the exact same part and brand (Gates must repackage) as the old stock one. Anyway, you can see below where the dust cover for the bearing on the old tensioner is completely missing. I don't know where or when it fell off.
A side shot of old and new.
This side seats against the engine block. If you look closely, you can see where the old tensioner pulley is off center. The shaft the it rotates on is bent but it still rotated, kind of.
Below is the belt from Gates. Looks good to me.
This is the box the tensioner came in.