bobbyjames

I received a report from the shop where I have my 2010 S63 Mercedes serviced that the A/C and the Alternator need to be replaced. Apparently the alternator was freezing intermittently and it sheared the safety break away in the A/C clutch. So now I was told that both the A/C compressor and the Alternator need to be replaced. I asked if they could just replace the A/C clutch since it was the part that was damaged. They said that Mercedes does not sell an A/C clutch as a separate part but I need to buy the entire A/C compressor and clutch as one unit. I will take the hit on the alternator but does anyone have experience in changing the A/C clutch? It seems ridiculous to believe that every other vehicle has a replacement A/C clutch except for Mercedes.

bobbyjames

Ok so here is some interesting info for W221 and M156 owners. I posted on the shear pin breaking away on my Denso AC compressor. The dealer will tell you that you cannot replace to pulley and you will have to purchase a new compressor.($1400 at the dealer) Mercedes uses the Denso AC compressor that will break the pulley away from the shaft on the compressor allowing the drive belt to spin if the compressor locks up. The bad news is apparently they have had problems with the alternators in the W221 and M156 and it will lock up intermittently which makes the AC believe that the compressor is freezing up and shears the pin and now your AC is out and you still need to replace the alternator. You can find the AC pulley complete for less than $150 on eBay. if you run into this problem contact me before you ruin the compressor like i did and have to replace the entire compressor. (no fun) I DIYd the entire project on my 2010 S63 so now I am a wellspring of knowledge and I could not find a post anywhere on the internet on how to do this.

Soylent Green

Well done figuring this out on your own. Should I have this problem I will contact you.