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A/C compressor clutch rotates when A/C is off

1996 Chevy S-10, 2.2L, 85K miles

I’ve had the A/C compressor bypassed for quite a while now (using a shorter serpentine belt), because the compressor clutch has always been very noisy and I think even dragging the engine a bit. I don’t think it’s the clutch bearing, but instead the pulley scraping against the front plate (or whatever its called). I could spray some WD-40 onto it and it would quiet down.

Today I thought I’d put the old belt back on and see if it had quieted down. Not only is it as noisy as ever, but now the entire clutch rotates a bit even when the A/C is turned off. Not much, perhaps one revolution per second. Unsurprisingly, the clutch doesn’t engage when you do turn the A/C on; it’s surely lost its refrigerant charge by now.

Are the compressor clutches on these things separately replaceable parts? I’ve looked everywhere and can’t find anyplace that has just a clutch; everyone seems to have entire compressors, but that’s not what I need. I also can’t locate any repair steps for clutch removal, even on ALLDATA. I imagine a special puller of some sort is needed.

My ARRC data base indicates clutch replacement possible. Instruction are quite lenghtly and special tools numerous. As with all jobs you do the first time I bet the steps can be reduced and the list of special tools shortened with experience.

I must find out how to post off this site,it may be restricted. Perhaps I can print them then scan then post.

I am suprised that a pay for service like ALLDATA omits these instructions

So what do you think. I printed the instructions from the ARRC data base that my College subscribes to (no restrictions,there was a button to allow you to print out the instructions) scanned them and save them to my flash,now I can attach them. My question,do you think this is allowed?

I have tried to post and I get a “to large” error message.Perhaps I can compress the files. I will keep trying. There is 8 pages of instructions and pictures that I scanned to Word 2007 and they are about 60kb each. I had my tech support guy look at the error message and he says it is related to the sites (CarTalk)restrictions,I will keep trying,I like a little challenge.My tech support says file compression wont help me.

Now I have flagged my own post

I honestly have no idea. I can’t imagine why car repair instructions would be restricted, particularly on a 13 year old vehicle. I guess that’s a call you’ll have to make.

I would be heading for the local salvage yard…

Yeah the clutches are separately replaceable but requires several tools and access to do it. I have not had any luck replacing the clutch alone since at that point the rest of the compressor is not far behind. The clutch is electro-magnetic so due to non use must be some kind of friction either rusted together or not fully disengaging or something. Short answer is forget it and just replace the unit with a junk yard one for $50 if you want to use the air again or just leave it the way it is.

That sounds reasonable to me. Is a junkyard compressor likely to be in decent shape? That’s not something I’d think to go to a yard for, but what do I know.

It’s not the clutch that’s failing. It’s the compressor pulley bearing that’s failing. That plate in front of the compressor pulley is the clutch plate. This is attached to the compressor shaft. The pulley bearing is mounted onto a boss casted into the compressor body. This bearing has failed where it’s allowing the pulley to come in contact with the clutch plate, causing it to turn intermittently.


When you price a “rebuilt” compressor, the junky will look even better. They will guarantee it for 30 days. If it lasts that long, it will last another year or two…

Like speed, cold air costs money. How much do you want to spend?

Yeah, isn’t that always the case? I’ve looked and they’re pricey…$200 at the minimum.

I’d like for the A/C to work, but I’m not really in the mood to spend hundreds and hundreds of $$ to do it. Even saying I do change out the compressor, there’s also the matter of finding where the refrigerant leaks out. At this point it’s probably many places; every seal and o-ring is suspect. And then there’s replacing the receiver/drier (pretty standard step, I understand), then paying a shop to do a proper evacuation/recharge…sure adds up fast.