White_Knuckles

I know the mystery noise could be most any spinning thing. The whirring only occurs on cold start-up and lasts about 15 seconds. The belt condition looks fine where I doubt it's the noise maker.

I have tried to isolate the source listening side to side but the sound telegraphs everywhere. Sounds like maybe a dry bearing, kind of a shhhhhhhh that fades. The engine must be cold to duplicate. I disconnected the mag clutch to the air pump (smog) no luck.

I thought I'd order a belt and maybe idler or tensioner pulleys that are common failure as unknown history. Reading posts about this there are many cautions on the change out procedure. I'd hate to down the car exploring the drive and have the tensioner disintegrate as others describe.

Looking for similar problems and what minimum on-hand parts you recommend for pulling the belt to access rotating things to isolate.