A/C Compressor Noise

My son just bought a 97' with only 61K. Car seems to be in ok shape. For some dumb reason he didn't even check the a/c. I had him run it for me and after the clutch ran for about 5-10 seconds there was a loud screeching noise. Turned it off and on several times. Now it takes about 15 seconds before that noise comes in to play. The A/C air is cold and the clutch operates so we have freon and adequate pressure. Is it a bad clutch or the compressor?

Does the noise occur whenever the A/C clutch is engaged, or only after it's been engaged about 15 seconds now? Try a quick spray of something like brake cleaner on the belt when it squeals. Does the noise change or go away momentarily? If so, you may just need a new belt and possibly a new belt tensioner. If you're not so lucky, it sounds like you may have an A/C compressor that is on the verge of seizing up.

And for what it's worth, "Freon" is a trademark name for DuPont R-12 (and sometimes DuPont R-22) refrigerant. Since your car is a 1994 or newer, it will have R-134a refrigerant. Granted, it is pretty much widely accepted to refer to all forms of refrigerant as "Freon," I just like to nit-pick. :)

-Rod

It does take about 10-15 seconds after the clutch engages that the noise comes. The belt was replaced the day before he got it and I checked the tensioner Gage and it falls right in range. The noise is piercing and I agree it sounds like the compressor is ready to seize.

I suppose another thing you could try would be to unplug the compressor, then turn on the A/C. If the noise still sounds after the 10-15 second timeframe, you might have a bushing issue in the cooling fan behind the radiator.

-Rod

I am almost certain it is the compressor. Probably a clutch plate issue as it sounds like metal to metal grinding and I had that problem with my Bonneville. I just wonder since it takes a good 10-15 seconds once it engages to make that noise. With the Bonny it started right away.

Just to be sure, have you put a gauge on the AC to be sure you have the right ammount of Freon(R) in it?

Freon is a registered trademare of DuPont corporation. :iceslolan

An old Indian trick: When I'm confused about a noise source I take a long screwdriver and put the handle to my ear then put the end on the compressor, or whatever, and usually hear it in spades. Be careful and don't put it on anything moving like the belt. You can probably trade the compressor in for a core credit, but don't run it 'til it tears up 'cause it won't be worth a plug nickel.

An old Indian trick: When I'm confused about a noise source I take a long screwdriver and put the handle to my ear then put the end on the compressor, or whatever, and usually hear it in spades. Be careful and don't put it on anything moving like the belt. You can probably trade the compressor in for a core credit, but don't run it 'til it tears up 'cause it won't be worth a plug nickel.
Another indian trick that works just as well: use a piece of fuel line (please make sure it has not been used! :screwy:) to find the noise, stick one end in your ear and move the other end around near where you think the noise is coming from. This will usually get you rignt there near the problem. Plus, if the tube gets caught in something, you can just let it pull away, vs. getting into the fight of the century with a screwdriver that has a reach advantage. :popcorn::rofl: