Screeching AC belt (intermittent)

When I turn on my AC, I get a screeching noise for a few seconds that goes up in pitch and then goes away. It repeats the sound at pretty regular intervals every few minutes. It does not happen when AC is off. The AC belt is brand new. How can I know if this is a problem with the compressor clutch or the compressor itself?

If it's just the compressor clutch, can it be removed to repair/replace without removing the entire compressor and opening the AC lines?

Also, while this is happening, the AC is blowing cold air just fine.

 

Yes the clutch can be removed without opening the system and it’s not too hard on the 3rz. You can unbolt the compressor and there is enough slack in the lines where you can lift the compressor and have the clutch facing you. I believe it’s a 10mm bolt that holds the clutch on (break that loose before you remove the belt) and a snap ring that is a tie-dyed bitch to remove. Be careful when you remove the clutch because there are shims that need to on in the same order that come off.

 

Thanks for that info. I appreciate it.

 

More than likely it’s the AC idler pulley, check that 1st.
My pulley has gone out a few times

 

Mines rusted to heck. Need to replace it probably.

 

Either that or out of adjustment or both lol

 

Well, it turns fine I'm pretty sure. But when I went to change the belts, I couldn't get the darn tensioner to slide any where. The adjustment bolt would go in and out, with a lot of resistance bc its rusty, but the darn pully wouldn't slide to loosen up. (I stupidly later realized that maybe I'm supposed to loosen the center bolt on the pully to get it to slide). Any way, I slid it enough with a dang mallet to get the belt stretched on and tightened it up. I was in a frustrated rush at the time. I'll revisit this. My PS pully is janky too, but not presenting any issues. These are like, lingering incidental issues left to do after doing a lot of work on truck overall.