As planned, I worked on the air conditioning system. The goal was to replace the original compressor by a modern and more gentle one (for the timing chains), replace the drying cartridge and then try to put the system back in working order.
I also had a problem with the air conditioning fan, which was working only when he wanted, and he usually didn’t want to. I quickly found the problem, it was a bad contact on the connection of the capacitor associated with the fan, because when I connected the fan directly, without the capacitor, everything was working correctly.
Once the compressor installed and the fan back in working order, I went to see an air conditioning specialist. He couldn’t find the right drying cartridge, which must be replaced, but he found me a part distributor who let me search in his catalogs and I found the right part using the catalog pictures. The day after, the cartridge was delivered and a few days later I was back with the air conditioning specialist.
There was some progress but it doesn’t work yet. I’m glad that I found a drying cartridge quickly, it’s not easy here because of course local part distributors never find any reference to the SM in their part catalogs. But there is a leak, fortunately this one was easy to locate.

So I need to replace the leaking pipe, I’ll probably replace all pipes, but the problem is that I’m not able to remove this pipe for the moment because its connection on the evaporator is made of brass and could brake easily if I apply the required force with a wrench.