Smoked the AC compressor clutch, literally

[kellen302]

Alright, so I rebuilt everything on my '86 CS AC last summer and converted to R-134a, using NOS parts where available, including the official retrofit condenser (and the official sticker). Aside from vacuum leak issues, the AC has been flawless, blowing cold even idling in hot traffic.
However, yesterday it was around 110° and I decided to go to home depot and the mall to get dinner because it was 85 inside. On m way there, the AC stopped blowing cold at a stop light, I saw a hint of smoke and smelled burning. Expecting the Alternator to be combusting I pulled over as soon as I was able in two blocks and shut it down. When I popped the hood there was smoke coming off of the clutch, some visible scorching or lubricant that had flung out of the air gap, and when I spit on the clutch it boiled off instantly, the compressor did not boil anything off, it was just normal compressor temperature.
I started it with the AC off and everything seemed to be fine, when I tried engaging the AC there was occassional flecks coming out of the clutch and it sounded different than it previously did with the AC running, but cold air did come out of the vents.
The clutch was a UAC part from Rock Auto that I have already applied for a warranty return on, but the compressor is NOS off ebay and I really hope it didn't get damaged. Has anyone dealt with this before? I would do more troubleshooting but it is 115 today and tomorrow so I am stuck inside.

Thanks!

[sly]

Usually when the clutch goes, the compressor is fine as the clutch will slip and destroy itself but the compressor just sees lack of rotation.

[Mainemantom]

I had that happen a few times when I lived in the desert. As said above, generally compressor is ok. If you can get a Motorcraft replacement that is a better choice.
You guys almost never get that hot. It isn't even August.

[ZackN920]

I had something like that happen on my 01 Cherokee, but the clutch on mine was glowing bright red, and when I shut the engine down the belt snapped. In my case the bearing failed.

Just a curiosity. Are the clutch plates adjustable on these compressors? If they are, they should be periodically checked for clearance. That would help avoid burning it up, as long as the compressor isn't overly stiff. Something to also check if ya put a new one on. Just to make sure it's at spec.

[kellen302]

I appreciate the tips, calms my frayed nerves (115° does that) The warranty replacement clutch is on the way but I will keep an eye out for a Motorcraft unit. Firm believer in original parts and quality.
The clutch gap is adjustable via shims in the kit. I set it to spec when I installed it but I will definitley give it some more routine checks after I replace it.
Our weather is breaking aaaalllll of the records. Same as our ice storm in February and fires in September (metro Portland under evac). You might say this climate change thing is heating up....

[VicCrownVic]

I went through a few clutches on my '89.
+1, the compressor should be fine.

[kellen302]

Looks like RockAuto carries the motorcraft parts, just as separate pieces instead of one clutch "kit". I'll run this warranty replacement but if it gives me any more hassle I'll just get the Motorcraft one. Wish they had it in stock when I did this the first time.

[gadget73]

Will the front plate on the clutch spin by hand? If it does, the compressor is fine. If it does not, the compressor locked up and thats the real problem.

would be worth verifying the fan clutch is good. Lack of airflow makes for very high head pressure and it works the hell out of the compressor. There is a high pressure relief but offhand I don't know the pop pressure. Its fairly high though. if the orifice tube completely clogs, it will pop that valve and dump the refrigerant out. Had it happen on the Continental when I was messing with the AC initially.

[kellen302]

Compressor spins by hand, I've got a new belt to put on it as well. And I'll probabably do a fan clutch this summer. Temps finally back down under 100 today, still almost 20 over where we should be normally.