M52 SWAP AC losing refrigeration Gas

[sindako]

Hello guys.
it's been so long.

my car had an alpina c2 2.7 in it. and the AC was running like a charm and it was so cool.

the engine blown and i swapped into an m52.

anyways.
i installed everything right. and even got the AC hoses retro fitted.
I installed it right and even wired it to the dme for the rpm.

I pressurised the system up to 300psi using nitrogen to test for any leaks. and nothing eas leaking at all. thr clamps, the hoses everything is tight and no leaks.

so i oiled the system using refrigeration oil, then i dryed the system with methanol, vacuumed the system and filled the system with R134a.
@ 40psi on low valve and 220psi on high valve.

it ran for a day and the refrigerant just went off.
i changed thr o rings on the compressor and used new ones. and now leaking.

it only leaks gas after i turn in the AC.

I am thibkibg it could be the Compressor itself leaking from one of the seals inside. or thr seal in between the compressor shaft and the piston system.

also the compressor idles at 40psi and the needle on the gauge shakes while running the ac..

bad compressor?
anybody had that problem before?
should i get a new compressor?