533i strange noise

["Smith, Robert III" <RS9W@xxxxxxxxxxxxxxxxxxxxxxxx>]

     I have this strange noise originating from the front of the engine that
only surfaces at a certain RPM, 1.5K to 2.0k.  I have localized the noise to
the water pump area, I think.  What does a failing water pump or alternator
sound like? I,  at first,  thought it was a belt problem.  Upon inspection
the belts need replacing and I will have them replaced next Wednesday.
However my mechanic feels that it is not a belt problem but rather an ailing
alternator of water pump.
Greatly appreciate your collective assistance on this one.
Thanks

Robert Smith III
1984 533I  138,000 miles 

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