Darren Mills

Hi, this is my first post after a long time looking. Hopefully somebody has some ideas.
Ok ive an audi A6, 2.0 tdi, 2009, 130,000 miles.
A squeak started from the serpentine belt. It was discovered that the alternator clutch pulley was seized. It was replaced and 5 min into driving it the squeel came back. 5 min after that after getting back to my driveway the belt snapped and came off. The belt was ridiculously hot and the new clutch pulley seized again.
the mechanic took the alternator off and had it checked. The alternator guy replaced the rear bearing and fitted q second clutch bearing.
All was put back together with a new belt. All other pulleys turn free with no wobble. The belt screaches still. Turn off car before belt is damaged. Im told the belt is on correctly on all pulleys. All accessorys turning clockwise.
he replaced the belt tensioner next. Exact same problem.
He's stuck for ideas as am I. I really need this car back on the road. Can anybody come up with some ideas as to why the belt is screeching to the point of destruction and to why one new alternator clutch pulley seized in 10 min of operation.

​​​​​​Thanks for any responses in advance.
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