fiat doblo jtd 75,000 miles strange noise from fan belt area.Changed pulley wheel this didn t help.Next stop alternator this did help but still strange rattling noise.Before i go any further e.g power steering has anybody else had this problem.We own three all similar millage with no faults.When the fan belt is removed no noise,(water pump is not driven by fanbelt).Any help would be
gratefully received.Forgot to say noise only evident at tick-over speeds.

ruber damper in crankshaft pully failure comon fault

Yes I have the same problem but only from cold. New belt and pulleys and water pump.Once warm not a problem.

Are you sure there's nothing leaking on the belt that's drying up when the engine is warm?

Common fault on Ford Fiesta, power steering fluid weep from a connecting tube runs down tube and lands on belt causes slight squeak when cold, evaporates when warm.