Last year I noticed the compressor on my 85 380SE squealing some times when I turned on the a/c. Now it seems to be stuck and the belt starts to get hot and smoke when I turn it on. Is the compressor done or just maybe the clutch? Would I be better off replacing the whole unit? Thoughts...
1985 380 SE 200,600 miles

I am not an expert but have learned more than I want to know about A/C systems in the last 4 months. I am almost sure your compressor died a "Black Death" and is seized internally. With your engine cool, grab the front of your compressor and see if you can turn it. You probably can't or might be able to turn with extreme force. If this is the case you need a replacement compressor. As for the clutch is is a 50/50 chance it has some damage. If it were my car I would replace both clutch and compressor along with at least the drier and make sure you get it flushed thouroughly by a GOOD A/C mechanic.

I bought a rebuilt compressor and new drier from fastlane parts (this forum sponsor) pretty cheap and installed them on my little '81 380sl. Had shop flush and refill with 134a after a good vacuum and system is great. check out www.id-usa.com
You can get an 0-ring pack most any parts house or at fastlane (I suppose).