Driving a '99 I30 that just passed 150K miles. No issues at all until last month when the radiator cracked and it overheated. I got it shut down before any lasting damage occured, and it's now got a new radiator, hoses, thermostat, water pump, temp sensor, and a new temp gauge is on order (all DIY). Only had it back on the road for a week when the p/s belt broke. Installing a new one I found that the crankshaft pulley was broken. That's a special order part, so while I was waiting for it to come in I replaced my leaky valve cover gaskets. My pulley arrived and was installed yesterday. Now I have a fairly loud and alarming squeal/grinding noise coming from my a/c compressor. The pitch changes when the clutch engages, and the system still produces cold air (although it has been getting weaker). I'm thinking that a new a/c clutch is on the near horizon, and I have a few questions for the crowd...

I've heard that the clutch can be changed without removing the compressor (and having to evac the system). Anyone done this before?

Does anyone know a good source for a clutch and/or compressor? Or how much I should be looking at spending?

Thanks in advance for the assistance!

Update: Found a thorough write-up for this issue, though some of the vendor info was outdated. Pretty much followed the FSM. I borrowed the A/C Clutch Puller from Autozone. I'll be shipping my clutch assembly to a shop in Florida, Polar Bear Inc, tomorrow morning. They quoted me $229 for a reman compressor w/clutch, but I'm going to try this first so I don't have to open the system. I could probably have the bearing replaced at a local machine shop, but decided against it for two reasons. There are several (4?) variations of this A/C (99 Maxima/I30) and I don't want to spend a lot if time finding the right bearing, and Polar Bear can perform any other repairs if they find anything else wrong.

I'm glad you found the write-up. If you break the AC line, make sure you replace the dryer.

Thanks for the tip. I'll be hooking up the gauges once it's back together to see how it looks. I've read a lot of posts that recommend keeping the proper amount of oil in the system, but I don't understand how to check/service it. The FSM didn't really help me, either.

If I do break the line, most likely to replace the compressor, what precautions do I need to take to minimize the amount of moisture that gets introduced to the system? I assume that once the refrigerant is recovered from the system the compressor shouldn't be run, and that the time the lines are disconnected should be kept to a minimum.

Seal the opening as much as you could - plastic or latex gloves around opening with rubber bands or electrical tape will do the job. The FSM should indicate the amount of oil needed in the compressor. After components are replaced, the system must be evacuated again and tested for leak. If Ok, refrigerant can then be added. This is best handled by certified HVAC technician which has the right equipment.

You can get the AC guages at Auto Zone
You might look at the FSM to see what the high side and low side PSI readings are
and correlate them back to the FSM
I had low PSI on the high side but the AC shop was able to make my compressor limp
along. Its ok when the temp outside is <95 degrees but after that its cooling ability
lessens. So its easy to look at your system with the guages but once you open it up
you have to evacuate and refill properly.

Got the clutch back and installed today. The repair cost me $65 for a new bearing and smoothing out the clutch surfaces. Thanks to everyone for the suggestions, I'll be hooking up the gauges next to check the system.