2005 Nissan Xterra Engine Bay Noise


Test Drive
Ketchum, ID
Trying to identify this noise. 2005 Nissan Xterra. 21K miles (not a typo), but of course it's 17 years old. The noise seems to be coming from the left side, in the vicinity of AC compressor or the alternator (so bearings?) Or could it be the belt? (Seems like not.) If I need to diagnose more, what's the strategy? Remove the belt and move things by hand and see what makes noises? When I was a kid in the 70s, this would have been a bad water pump noise, but I believe the water pump is driven by the timing chain, and this definitely sounds external. Thanks

View: https://www.youtube.com/watch?v=sOP7SNlTbU4