AC compressor clutch

[samprix]

I have a 1999 lesabre with 136000 miles. Recently with the AC off I have been hearing a light grinding sound under the hood. The grinding stops when the AC is turned on. I assume that there is a problem with AC compressor clutch. It seems that the clutch does not fully disengage when the AC is turned off. Does anyone know of a fix for this or does the compressor need replaced?

[HotZ28]

Have you removed the serpentine belt and checked the WP, PS & all idlers to isolate the noise? With the A/C clutch engaged, it pulls an extra load on the driven accessories and may dampen/muffle the real problem. In addition, you can check the compressor clutch clearance with the A/C OFF and should be about .025-.045 max. If less, it may be dragging, but I would check all other possibility's first.

[samprix]

Thanks for your response.
The clutch is definately dragging while disengaged.
Does this mean that the whole compressor needs replaced?

[Hooyah]

If it's just the clutch you should be able to do that while it's still connected to the vehicle. I just did an ac overhaul on my 97 lesabre.

You have to unplug the clutch on compressor, and maybe the low pressure sensor (on the line connected to back of the compressor). There are three 13mm bolts on the front and one on the back of the compressor. Unbolt them and you might be able to get enough room to do the job. I actually did it with the compressor removed from the vehicle, but I also have a vacuum pump and gauge manifold.

Anyways, there's a bolt in the center of the clutch that has to come off, you need a tool to keep the clutch from spinning while you remove it. Next the clutch is pressed on so you also need a puller/installer. If you do the pulley also there is a snap ring that needs to be removed.

To reinstall the clutch make sure you know the correct air gap (can use a feeler gauge in three places around clutch). If you dont have an installer put a rag over the clutch face and use a pipe and hammer to bang it on. Installer is better though. Then just hold it still with the clutch tool while you reinstall the center bolt.

Reinstall compressor on vehicle and you are done.

[brcidd]

This sounds like classic v-5 clutch drag- the air gap has tightened and needs to be adjusted back to .020" . I have answered this several times- and usually see about 1 a week during the hot season. The noise is a scrapping/rattle only with a/c off- should see signs of metal shavings about the clutch hub. The fix is to borrow the installer/removal tool from autozone and back off the air gap a tad. This can be done on car, without removing compressor or refrigerant, and can even be done without removing the shaft nut since the nut does not bottom on the clutch drive. Pull back the plastic cover in wheel well to access