how can i tell? the ac pully freewheels when ac isnt on... will engage when i turn the ac on but it almost as if the system locks up about 20 seconds after engaging... the belt slips over the ac pully......

bad clutch or is the compressor on the way out??

I would question the condition of your serpentine belt first.

If the compressor siezed intermittently, you should have billows of smoke from either the clutch or the inside face of the belt.

Steve

probably the belt...i used to do a litte a/c work on the old R-12 days, before you needed a license to service cars. and you would have to run some water from a hose on the condensor coil(the one thats infront of the radiator) to keep the head pressure down so you could add freon to the system.. you had to watch it that you did not get the belt wet or the belt would slip and not turn the a/c compressor.. you probably either have a dirty or bad belt.. it takes alot of pressure to turn the compressor on a car..
or i would check the adjuster to see if the needle is in the center(if its on either side it means the belt is stretched and this would let it slip.... hope this helps.

my brother and i just changed my water pump, timing belt, serpentine, and tensioner not too long ago, and just recently i bought r134a to put in my car. after i added the r134a, whenever the compressor kicks on, it chirps the belt at idle. i asked one of the dudes my brother works with that does a/c all the time, and he said the compressor (not the clutch) is on the way out. my a/c system had very little pressure, so i think a previous owner just vented it off to keep the belt from squealing, or maybe i need a shot of oil, but my brother told me i should never need to add oil to a working system.