Rattling noise in AC compressor

[gln7]

There's a clattering/rattling noise coming from my AC compressor on my '95 Lumina APV, 3.8 engine. The noise starts as soon as the van is started, even with the AC off. When I turn the AC on, the clattering speeds up. Would this be the clutch gone bad? If so, can the clutch be replaced without getting a whole new compressor? Thanks.

[SUPERDAVE22]

Could be that or the compressor bearings going bad

[gln7]

Thanks. Is it safe to drive it like this, or could it damage my drivebelt?

[LMP]

First, I'd bypass the a/c with a shorter belt. THis will give time to investigate.
With A/C the serpentine belt is 102.5", PN 1025K6. With out A/C the belt is 72.5", 30" shorter, PN 725K6. (based on '93 3800..should be similar)
www.avigex.ca/xport/serpentinebelt.jpg

MOst of the time, the free wheeling bearing is the culprit, but then the noise stops when the a/c is ON....and check if it really comes ON when you turn the A/C ON, as a loss of refrigerant pressure will prevent operation anmd the noise would continue...

From the wheel well, you can remove the inner plastic cover and then rotate pulley by hand . Free wheeling bearing can be changed from there.
Noise cannot be the same running and not running: when a/c is not engaged, only free wheeling pulley rotates, involving free wheeling bearing and possibly damaged friction clutch . Inner bearing and compressor itself do not rotate than. ONce a/c clutch is actually engaged, then inner bearing and compressor will rotate, but then free wheeling bearing and friction clutch are noiseless. Possibly, the clutch material can be damaged and protruding, making noise against the free wheeling pulley when off, and touching other components when rotating.

[gln7]

Thanks for the info, LMP. Will try the short belt and go from there.

[LMP]

...and notice that the a/c is turned ON without your knowing whenever MAX COOL(recirculate), DEF or HEAT/DEF is chosen, except when temperatures are below freezing.