Last weekend I took the C4 out for a spin and the climate control completely shut off. Shortly after I also noticed a burning smell while at a stoplight. (If I smell burning in traffic in my other cars I automatically dismiss it and assume it isn’t me, but in the C4 my first thought was uh-oh...what’s burning? Lol)
Anyway, got it home and popped the hood and found the AC clutch and surrounding area covered in bits of charred and melted plastic. It turns out the AC pulley bearing had disintegrated to the point it allowed the pulley to walk on the shaft and make contact with the AC coil. The burnt plastic was the plastic coating from the coil all rubbed off and burnt up from rubbing the against the pulley.
I got a chance to dig into it today. Here’s what was left of the original bearing after it basically fell apart.


The coil doesn’t look much better. You can see how the plastic coating is gone and the copper coils are all exposed.


That’s what caused the climate controls to shut off because the coils made contact with the inside of the pulley and blew the fuse. For now, I was able to get a replacement bearing locally so I put a new bearing in the pulley and put it back together with just the pulley on the shaft but left the coil and the rest of the AC clutch off. So it can be driven but just doesn’t have AC right now. I found a replacement coil from a wholesale supplier online for $30 shipped so once that comes in I’ll pop the pulley back off and hopefully get it all back together with working AC again.

Yeah really it’s not that bad at all. Just crazy how bad that bearing was! I had been experiencing a slight problem with the idle bogging a bit when the AC engaged, I have a feeling that the all but non-existent bearing was causing more than just a little parasitic drag...lol. All in I’ll only have about $50 into the cost of the bearing and the new coil. I also had to disconnect the AC lines on the compressor to get the pulley off, so I’ll need a couple cans of refrigerant to recharge the system as well.

I’ll find out. My new coil came in the other day so once I get time to put it back together I’ll update with the results. The coil and bearing were cheap enough I figured I’d try this first before replacing the whole thing.

What year is your car? On the LT1 the coil is a stationary piece that doesn’t rotate or move in any way, but I don’t know anything about how the compressors on the L98’s or crossfire are built.

Well I got it all buttoned up and recharged the AC tonight and so far it all seems back to normal. The AC clutch engages smoothly and it’s blowing cold air on command, so that’s a good sign! The coil I got was from a wholesale supply house for AC parts and although it was correct for the compressor it wasn’t necessarily a Vette specific part. As such it wasn’t 100% plug and play, but nothing too difficult either. The wiring harness had to be swapped from the original coil, and there was a small locator hole on the old coil housing that wasn’t there on the new one. The hole lines up with a metal pin on the compressor housing and it locks the coil in place so it can’t spin. I just had to copy the location of the hole onto the new coil and drill it out, no big deal. I’m happy to have functioning AC again and no more burnt up/binding bearing for about a $50 investment. It sure beats buying a whole new clutch or compressor.