The good news is that the problem's fixed and there is no more noise.
The bad news is that I absolutely wasted $500 in fixing it, to include the alternator that was thought to be the absolute cure. I needed to step back and re-evaluate my trouble shooting thought process.
Known fact:
The noise completely went away when the alternator/water pump
drive belt was removed.
Known fact:
The replacement of the water pump and alternator had no effect
on the noise.
What the he!! else could it be?? What's left in the accessory drive circuit? Ahhh ... the single groove crank pulley. Could it be? I jacked the car to have a look. All 3 pulley retaining bolts were a tad loose. I pulled the bolts and the pulley. All three pulley holes were slightly egged out and you could see witness marks where the pulley had been rocking right to left, same on the bolts too. It appeared I'd finally found the problem.
The pulley is a factory stamped steel single groove pulley, part number: C8AE-6A312-B. It measures 6 3/4" in diameter and coupled with my 6" single groove March water pump pulley gives me the water pump overdrive that a cooling challenged FE does so crave.
I got on the 'puter and did a search on Flea Bay along with Mr Google and came up with a couple used pulleys with holes as wallowed out as mine. March's pullies are only 5 1/2" in diameter, with them I'd be going from over driven to under driven. That won't work. I could find no re-pops of the OEM one either. At that time I decided to rework and reuse the one I had. I re-flattened the contact face of the pulley, grabbed 3 new grade 8 bolts, flat and lock washers. I put some blue loc-tite on the bolts and tightened up everything up. All's quite now, quieter than it's been in a very long time.
I might have a "gently" used Ebok water pump and 140 amp chromed-out Power Master 1 or 3 wire "SI" GM alternator to post on the "Pay It Forward" thread in the very near future.
