Good afternoon,

I have a 2003 BMW X5 3.0 with 150,000 miles. I have a noise belt issue which I believe is caused by a misalignment of the alternator . . I'm not sure but this is the issue below.

Has anyone had a serpentine belt issue where the belt comes off the water pump pulley to the idler pulley and is not sitting completley on the idler pulley. 90% of the belt is on the idler pulley and a small 3/16 inch strip hangs off the edge of pulley. This causes the belt to wear very funny thus after 6 months a belt noise really develops. I use a Contitech belt.

I've replaced belt tensioners, idler pulley, water-pump pulley and have checked to ensure all is tight and correct. I do have a newish Water Pump (High Performance Stewart 2 years old).

Could this have anything to do with Alternator pulleys being out of alignment? Is this theory possible?

Cheers,
Chris