BMW 523 i 98 A/C problem

[Balaburski]

Dear Sirs,
After starting of the engine with A/C on, a noise of grinding of metal appeared from the compresor of the aiconditioner. The cooling is ok and these sound disappeared after few miles.Also sometimes when the cabin is very hot from the syn,the A/C dont want to go on.Is this some protection of the compresor from the thermic strees?
Pls I"m looking forward to heard from you!
Regards ,Balaburski

 

[Montana]

The grinding noise is most likely a result of leaking lubricant. It may go away after a few minutes after the remaining fluid has a chance to circulate more. Look under the hood. Do you see any sign of a fluid spray pattern on the engine compartment or hood near the head of the compressor?

I'm not sure there is much you can do except run it until it finally fails then replace it.

As far as the AC not coming on when it is very hot, not sure there. AC systems will usually not engage if the "freon" is under OR over pressured.