AC Clutch Grind
 

Hello everyone, I greatly need you guys assistance and suggestions.

Basically a couple months ago, my car used to make this grinding noise, the problem was intermittent. Now the problem came back in the winter and it hasn't faded away like before. I narrowed the problem to my AC clutch, I do not know if it is the whole clutch of just the bearing, I figured it was just easier to replace the whole clutch since it has the bearing included.

Also, a couple weeks ago when I would press the AC button, I would here it kick in. Just now I tried to test the AC to see if the clutch kicked in, the clutch would not engage.

What could be the problem of this? Could it be that the AC clutch is just in its entirely, going bad and causing it to not engage? Was it caused because I let the noise happen for a while now and it just eventually messed with the clutch?

Thank you guys, your advices are greatly appreciated!


2000 Grand Prix GT

Kinda sounds like this:

Start by checking the compressor's clutch gap using a feeler gauge.
This link will help.
https://www.gmforum.com/mechanical-1...-plate-278951/
What is your gap size?
Also often the AC compressor will not engage until it is above 38 -40 F degrees outside.

I do not know the gap size for sure but it looks normal, now my AC will not turn on ( I dont see the clutch engaging). Could it be because the clutch is just entirely bad? I dont wanna replace the clutch but in the end, my compressor is bad or something

I edited my post regrading temperature, is it above 38F outside?

It is 25F right now, its cold. What does this have to do with anything?

The compressor is computerized controlled and to prevent freeze ups, it wont engage until it is above 38F.

Omg that makes sense dude, it recently got cold in Georgia so its been below 35F lately, I just tried to start the AC and it would not engage dude. So how does it know the temperature? So I am guessing my AC system is still good and all I need to replace is the clutch?

Where can I also find that information?

Car has sensors, info in FSM, factory service manual.
Measure the clutch gap to start with, it has to be specific, and will rattle if it is out of spec ..did you see the link I posted? I had to adjust mine.
Often rust build up between gap, I use emery cloth type sandpaper in between to get it cleaned up, and use a bit of silicone spray, keep it smooth & quiet.
You still may need to just replace the clutch & coil in there.

I do not have a feeler gauge, but I will purchase one tomorrow to see what is it. Thanks on the advice for the AC not engaging too, cleared up some worries because it is freezing outside.

Also for the gap you are talking about, it is still making the noise even though I do not see the whole clutch moving.

If it is still rattling while clutch is not engaged, then it probably is a bad bearing, requiring a compressor replacement.
That being said it is often difficult to pinpoint noises, and I like to use an auto stethoscope, to guarantee it is not coming from another accessory pulley.

Yes, the clutch is not engaged so it is making the noise. If the bearing is bad, can't I just purchase this: http://contentinfo.autozone.com/znet.../1121/image/4/

That will replace the whole clutch so I can avoid buying a new compressor

With the car obviously not running, grab a hold of the AC pulley and pull hard up/down/side to side, and see if you can feel any movement..movement= get a new compressor.

Soft Ride is correct........if the temp outside is below 35-40F, the PCM will prevent the clutch from engaging.......there are several ways it realizes it.....some auto HVAC systems have an outside ambient temp sensor, which would not allow clutch engagement......when the car first starts, intake air temp sensor and the coolant sensor, should be equal and the PCM will know ambient air temp on startup, so it will not allow clutch engagement under a certain temp.....also, most cars now use a pressure sensor......with cold temps, this will lower the pressure in the refrigerant lines, and if pressure is too low, it won't allow clutch operation...

As for your noise, if it is grinding when the clutch is not engages, and the noise goes away, when the the clutch engages, all you have is rust buildup between the clutch contact surface, and the mating surface of the clutch pulley....

Two things you can try:

I take some sand paper, and I slide it between the clutch and pulley(naturally you don't do this while the engine is running, :))......and I work my way around the pulley, making sure I get both the pulley and the clutch surfaces.....sometimes you can fold the sandpaper in half, and get both sides at the same time....sometimes, the gap is too tight, so you use one side, go around, then reverse the paper, and go around again.....then using an air hose, blow out any loose rust.........this has worked for me in situations where the rust was not that bad....

Second thing you can do, is rent a clutch removal tool, and increase the gap of the clutch plate from the pulley, by a few thousands of an inch.......

Thanks for the help guys, I bought a new ac clutch and it came with a new pulley and the bearing inside. My old AC clutch bearing is bad, I took off the belts and spun the pulley, it made the noise. I tried to install everything to day by myself, I had no room to remove the ac hub so i am taking it to my mechanic tomorrow to get the part installed. Also, my AC works too! yay, it was warm out today