serpentine

Hey guys, I have a 2001 e46 with 150,000 miles. For a few months I've had this screeching sound coming from under the hood. At first the sound would be intermittent for about two minutes and then go away. The weird thing is that sometimes the sound would happen and then other days it wouldn't...

I've seen no problems with the car, but then last night I pulled into the driveway, turned it off for 60 seconds, turned it back on, and snap goes my serpentine belt. I don't know how old it was but it didn't look really worn out enough to break. I'm guessing a pulley locked up, but all of them...

So my serpentine belt started with a really annoying squeak that gets louder as the motor revs. My first though was a bearing is bad, I replaced the water pump, rebuilt alternator, replaced the idler pulley, the tensioner pulley, and the I disassembled the power steering pump and everything...

My lame A$$ was "attempting" to replace both belts under the hood and I mistakenly turned the wrong bolt clockwise thinking it was the tensioned. I do not know what this bolt holds but the pic included shows where it is (directly obove the ratchet under the small circular dust cap). What did I...