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Bad clutch or compressor??

JerryHughes on Mon May 19, 2008 1:25 PM User is offlineView users profile

Year: 1997
Make: Saturn
Model: SL
Engine Size: 1.9L
Refrigerant Type: R-134a
Ambient Temp: ?
Pressure Low: ?
Pressure High: ?
Country of Origin: United States

I've been reading through the past posts on the forum and I'm not sure if the compressor went bad or if it's the compressor clutch but I'm afraid it's a bad compressor. A "grinding" noise has been coming from the compressor area for a while and just today there's more noise and a lot of vibration. There's a "resistance" when rotating the plastic end plate clutch disk. Before the clutch "probably" went bad I could rotate that with absolutely no resistance, quite easily. Now, I get resistance once-in-a-while when rotating, like something is dragging. (Actually, with one 360 degree rotation of the plastic end clutch plate, I feel resistance 4-5 times, equally spaced through that rotation.) But since the air coming out of the vents inside the car is still cold when the car is running, I assumed that the clutch was bad. I also observe a difference in the distance between the outside edge of the plastic clutch plate and the compressor pulley area, when spinning the clutch plate. It looks like the clutch plate "disk" is warped.

Would anyone know if that's a bad clutch? And even if it is just the clutch, since the car has over 155K and still has the original compressor, I think I may as well change the compressor (which would come with a new clutch) even if it's a rebuilt compressor. But if it is a bad compressor, even though the compressor hasn't gone all the way yet, if fixing, will I need to have the system flushed, a new expansion valve installed and a new drier too? (Just put in a new drier last month.) Any info is greatly appreciated.


mk378 on Mon May 19, 2008 2:08 PM User is offline

Do you hear the noise all the time the engine is running, or only when the A/C is engaged, or only when it is off?

A slight drag when turning a compressor by hand is normal. The pistons move up and down periodically as the shaft rotates. If it is getting stiffer over time though that could mean you are running without enough oil. Was oil added to replace that which was in the drier that came out?

Edited: Mon May 19, 2008 at 2:09 PM by mk378

GM Tech on Mon May 19, 2008 2:30 PM User is offline

Last Saturn I worked on had the pulley bearing spill all its balls on the floor when I took the clutch driver off- so it was a worn out pulley bearing- grinding with or without a/c-- that entire clutch assembly can be replaced- but your will need the clutch puller tool to remove that pressed on spline clutch driver- I had to fashion my own- took over an hr just to get the driver off--

Also no piston pulses in a rotany vane compressor such as yours the resistance is probably interference in the pulley or the like--

Spin the pulley with the belt off- see how smooth it is........

The number one A/C diagnostic tool there is- is to know how much refrigerant is in the system- this can only be done by recovering and weighing the refrigerant!!
Just a thought.... 65% of A/C failures in my 3200 car diagnostic database (GM vehicles) are due to loss of refrigerant due to a leak......

JerryHughes on Mon May 19, 2008 3:40 PM User is offlineView users profile

Hi mk378,

First of all, thank you for addressing my problem. I only hear the grinding when the air conditioning is on. When I changed the drier, I added one ounce of oil to the new drier. I was told that that was enough.

You see, the problem happened a couple of years ago. I had mistakenly loosened the drier connection to the condenser, heard the gas leaking out, then I quickly re-tightened that connection. Well, over time, the rest of the fluid leaked out, I suppose because the seal there wasn't good anymore. When the rest of the fluid leaked out, before the automatic or protective shut off to the compressor shut the compressor down, I started hearing that grinding noise---only not as loudly as I hear it now. So, I'm thinking that the auto shut off didn't work fast enough and the system got low on oil. So, last month when I installed the new drier, the noise was still there but I was hoping to get more life out of the compressor. So, the grinding may be a result of low oil and in that case, if I install a rebuilt compressor, will I have to have the system flushed or is there a possibility that the compressor (considering it's still running) didn't get bad enough to throw a bunch of junk into the system?


JerryHughes on Mon May 19, 2008 4:25 PM User is offlineView users profile

Thank you, G.M. tech, for answering my post. I just pulled the belt off the pulley and the pulley spins very freely. It's the clutch disk that doesn't spin freely. Does that indicate I have a bad clutch and not a compressor or pulley?? But again, considering the miles on the compressor/car (155K) I may just opt to install a rebuilt compressor even if the clutch is the only thing that is bad. In the long run it would only cost me $100 for labor to have the system re-charged. but in the end it may save a lot of grief. Thanks again,


JerryHughes on Tue May 20, 2008 8:44 AM User is offlineView users profile

P.S. If I do go the route of installing a rebuilt compressor, does oil come already inside the compressor or would I have to add my own and if so, how much oil? Thank you.


mk378 on Tue May 20, 2008 10:15 AM User is offline

Sounds like your compressor is going bad. The clutch is OK, the noise is coming from inside the compressor part. You should quit using it until you replace it. It's going to put more junk into the system the longer it runs. Most of it lands in the condenser since that is the first part after the compressor. I suggest replacing the condenser rather than trying to clean it. Also of course replace the receiver-drier.

The new compressor should come with instructions about oil. PAG oil absorbs water from the air. Thus even if the compressor comes with oil in it it is better to remove that oil and put in fresh oil right before installing it.

JerryHughes on Tue May 20, 2008 10:56 AM User is offlineView users profile

Thanks for the info, mk378. Much appreciated.


JerryHughes on Fri May 23, 2008 5:31 AM User is offlineView users profile

One last question before I take a look at the compressor oil to see if it's contaminated. Since I'm not sure I have a bad clutch or compressor, if I disconnect the compressor, or take it out, I can plug the lines so no moisture gets into the system, or the drier. However, this being just an "exploratory" thing, to see if the oil in the compressor is contaminated, because I can't afford a new compressor right now, after looking at the oil in the compressor, will I be able to hook everything back up, to keep moisture out of the system? Or, if the compressor oil is clean and it hasn't contaminated the system, I should only need a new compressor. Will I still need a new drier when the new compressor goes in in a couple of months even though I hooked everything back up? (I'll need the bad compressor hooked up, to run the serpentine belt) Thanks for any info.


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