Is my AC compressor sized up?

[John Reason]

I turned on the AC and it almost shut the truck off. Not 100 percent sure but I think my compressor has siezed up. I tried to turn the center part of the compressor by hand and it wouldn't budge. I did notice some rust around the clutch part of the compressor. Is there a chance to save it by spraying PB blaster into the clutch to tryand get it to break free or is his a lost cause? I bought the truck from someone else and the compressor actually looks in great shape other than the rust on the clutch.

 

[Charlie]

Well, you aren't the only one today. Turned mine on this afternoon, made loud noise and smoke. Shut it off. Will be replacing very soon. Weather getting hotter now. Wish I could give you some advice on yours, but I'm not experienced with AC system. Good luck.

 

[CorvairGeek]

If turning it on nearly stalls the engine, and all is good when turning it off, it is internal to the compressor. The pulley bearing would be an issue any time the engine is turning.