[strother]

A little background: my a/c was blowing warm air. Sight glass showed no freon. I took the car to the shop and had the system filled with r-12. Presto... Cold air.

A week or so later, I am driving with the A/C on. The air was cold one moment then warm the next. Later, I look in the engine bay, and the compressor belt has somehow slipped off of the pulley to the outside of the compressor. The belt is a little nicked now.

I'm at a DE when I notice this, so on my way out, I have a more talented mechanic put the belt on. System works again. Ice cold air.

A couple of hours later, a high, high pitched squeal came on. Only comes on when the A/C is on. It only does it at low RPMs, and I THINK only when the engine is cold.

I took a look in the engine bay with the engine running and the A/C off. Everything looks perfect. With the engine off, the compressor belt feels tight. When I turn the A/C on, the compressor belt vibrates a lot. More than vibrates... It looks like it is going to shake the entire engine out of the compartment. Then the noise happens. When it does, the entire compressor pulley stops spinning. Not just the clutch, the entire pulley. I would have thought the noise was the belt slipping, but no, the belt freezes too. The whole belt and pulley just stop, and the screeching squeal begins. Lasts a pretty short time -- 3 seconds or so, and happens at random intervals.

What gives?