Air Conditioning Noise

[Dynamic Entry]

Hi everyone, I have a very bad noise coming from the A/C clutch & compressor area.

I have searched and read threads for about 3-4 hours gathering info but haven't found any that address the exact situation I have had (not saying it hasn't been addressed but I haven't found it). For the record admin, search queries with just "AC" or "A/C" in the field yield no results at all. Is there a minimum character limitation for the search function?

Reading up did teach me a lot because I know nothing. Namely, I now understand that the clutch is what you see on the front face of the pulley attached to the compressor and that it engages the compressor when one of the four settings that use A/C are selected.

Here is my situation:

Yesterday I noticed a bad noise that occurs when RPM climb above ~2.5k. It is not a sound that I would describe as "knocking". I find it hard to describe but it sounds like a fast, consistent, clicking - but not high pitched. Kinda like sticking a hockey card in your BMX spokes but really LOUD. This noise occurred with the Bi-Lev setting selected and when testing, it didn't make a difference what setting the HVAC was on; the sound always occurred above the certain RPM. The air blew colder when I selected A/C so the unit is working.
Because the noise is happening when the compressor shouldn't be engaging I am wondering if it is an issue with the clutch. Unfortunately I took the belt off before reading that I could electronically bypass the system and before I really took a good look at the clutch.(I took the belt off before I knew the clutch was there). With the belt off, no noise occurs at any RPM so it for sure is occurring with some part of the A/C unit.

Can anyone realate? Anyone know what part needs replacing?

[Legacy777]

If you're getting the noise when the HVAC system is OFF or in BI-LEVEL, then the magnetic clutch is not disengaging (not too likely) or the bearing in the clutch is going.

Can you spin the outer portion of the clutch pulley by hand? That will tell you whether it's disengaged. If it is.....then it's probably the clutch bearings or something related to the clutch.

You may be able to replace the clutch, but you may not.....they're a real pain to get off. I'd personally just drive it.

[Dynamic Entry]

Josh, do you mean that you would just drive it without A/C or with the belt on and ignore the noise? I will likely cope with A/C belt disengaged for the next few months but come summer I will want to fix it. The noise is unbearable though, its louder than the rest of my motor noises combined.

Thanks for the info. I will check the clutch by hand and see what I can decipher.

[Legacy777]

I'd just drive it with the noise and have AC. Remember I've redone my AC so many times that I can do it in my sleep. I think I'm on my 4th compressor....and I bought a new one after having the used ones crap out on me....and talking with an AC shop saying that those compressors are shit!

Check the pulley by hand and report back.

[Dynamic Entry]

So the clutch spins freely by hand, no problem.

In one of the threads I read that it takes 6hp to power the A/C unit. Does this mean that by removing the belt I have effectively added 6hp?

Josh, you are in Texas so I can't truly appreciate your need for A/C, but I can't justify intentionally producing a noise like that for it. I will probably run without that belt for months on end. I guess if my heat was at stake I would feel differently though...... 0 degrees F here today

[Manarius]

In one of the threads I read that it takes 6hp to power the A/C unit. Does this mean that by removing the belt I have effectively added 6hp?

No. When you turn the A/C on, you lose 6hp...about.

It takes A/C to run the Defrost though so......consider that as well.

[Dynamic Entry]

Ya, I realized while I was working tonight that the 6hp would only be drawn when the compressor is running.

The Defrost still "works" in that it blows hot, it just has more moisture in the air = probably not as effective. Even with my A/C working I found condensation on the inside of the windshield problematic.

If it is a relatively easy fix I would do it soon but if the clutch is hard to fix aside from the whole unit I will be discouraged for now.