Alternator pulley gone missing
a couple of weeks ago (when the temperature dropped) my 156 1.9 JTD 16V had trouble starting in the morning. I knew the alternator pulley was on its way out since it started to make the horrible squeaking noise.
Last Sunday evening I decided to make a detour on my way home and try to fill the battery a bit, so I drove my Alfa up a nearby hill (approx. 30 min hill climb). Near the summit my ABS and VDC lights started coming on and off, I knew that meant critical battery voltage, so I turned around as soon as possible. About 2 minutes into the descend and after a loud bang, I lost power steering. As expected, the alternator pulley disintegrated and flew off, taking the AUX belt with it.
Last Monday I somehow managed to get the rest of the old pulley off and fitted a new one without having to take the alternator out. I was very happy with my car again, also took it to a car-electrician to confirm the battery was being charged.
Since I made only a couple short trips last week, I knew the battery wasn't at 100% yet. So yesterday, I took the car on the same hill-climb-trip. Half-way up, the battery light goes on, and the power steering goes off. A quick look under the bonnet confirmed that the aux belt is missing. Rather worryingly, so is the entire alternator pulley...
Has anybody ever heard of the alternator pulley unbolting itself and disappearing mid-drive? If I'm correct, the direction of the aux belt should "tighten" the pulley, should it ever get a bit loose... Is it possible, that the alternator seizes after a longer drive and the pulley is torn off? The thread on the alternator seems intact.
Thanks in advance for any help!