I'm having issues with the a/c clutch on a '71 cutlass supreme convertible. I've never had to work on an a/c unit, so I'm looking for some advice.

The pully on the a/c clutch spins OK. However, whenever the a/c gets engaged, the clutch locks tight and the fan belt just smokes across it (wonderfull smell). When the a/c is turned back off, the clutch spins freely again.

Normally I don't worry about it. With the car being a convertible I almost always have the top down anyway. It just bothers me.

Could this just be the bearings, or a problem with the clutch itself. A friend of mine said to just spray some silicone into it, but I would like some other opinions first.

 

Sounds to me like the compressor is locked up. The pulley spins freely when not engaged because the compressor shaft itself is not trying to rotate. Once the clutch is engaged, with the compressor locked, the belt slips and smokes.

Tim

 

^^^X2. Not good.

 

I think rebuilt compressors start around $200. Was the system charged and working before the problem? Original R12 or R134? AC repairs can be a slippery slope...

 

It's the original R-12 unit. It has never blown cold in the 6 months that I've owned the car. I was planning on having my local garage run a preasure test on it to check for leaks anyway. I just have not gotten to that yet while I was working on other things more important to keeping her on the road.
Like I said in the prior post, this is not a world ender for me since the car is a convertible anyway. It just bothers me that it does not work.

But on the bright side, it gives me something else to tinker with.