the pulley bearing is prob bad. When the compressor is on it sounds fine, but when off it makes a terrible grinding pulley noise most of the time, but not all the time.
Friggen internet.
Im gonna try this again.
Disconnect the plug from the ac compressor clutch and see if you get a grinding noise.
Check for any movement up down in out side to side on the clutch pulley.
Does it spin freely with no noise with the belt off.
Look for metal dust anywhere near the clutch.
Check the clutch air gap all of the way around with a feeler gauge.
Clean the outer clutch throughly and look for cracks or broken spring tabs loose rivets.
Check the thickness of that outer clutch face.
My old ac clutch is still about .170 thick
But only has about .010 before its digs into the rivets.
One of the 3 springs broke and it dragged and skipped on the clutch and overheated that spot enough that it cracked around a rivet and that rivet cocked sideways into the pulley side of the clutch.
It worked great with the ac on because that broken rivet stabbed into the clutch and grabbed.
As soon as I turned it of the wreckage chewed it all up and sounded like a bad bearing.
The bearing is fine.
I put a Murray 48656 reman ac clutch on my 94 about 8 years ago and it is still good.
But, it can be a real pain to do.
Three things make it difficult.
Removing the retaining ring that holds the pulley on.
Getting the pulley off without breaking the snout off of the compressor.
Setting the air gap
It takes a special tool which Oreillys used to have as a loaner.
The absolutely insane amount of time it takes to get that outer offshore piece of **** clutch face flat and trued to the hub in order to achieve what basically boils down to plus or minus .010.
Air gap is very critical.
80 buck part, 20 bucks for beer. 30 bucks for Scotch.
You can do it.
You just some calming zen when you do.