Now here's a thing.

Rather nasty tapping noise on cold start (colder = worse) which goes away once warm. This started just after the last service, which included replacement of belts (ancilliary drive belt and cam belt plus pulleys and water pump). Now I thought I'd got to the bottom of this, as a good squirt of engine oil on the business end of the alternator makes it go away temporarily. So, alternator bearing giving up the ghost as a result of the less "stretchy" new belt as a nailed-on cause I thought.

However, taking off the drive belt and rotating the alternator pulley by hand when cold, I can feel no evidence of excessive play in the bearing or roughness as it rotates. Feels like a new one.

So what do you reckon? Swap the alternator on spec or just leave it and see what happens? Any other possibilities as to source I may have missed?