Help On '87 Wagon A/c

[Motorhead]

I have been working on this 1987 Mercedes diesel wagon for a guy. It came to me with the A/C not working and the compressor front seal leaking profusely.

HERE IS WHAT I DID: I pulled the compressor and sent it out to a reputable place in Florida for a reseal and rebuild. It uses a small rotary type. I replaced the CONDENSOR, RECEIVER DRIER, EXPANSION VALVE. I blew out all of the lines.
I added the recommended amount of refrigerant oil. I evacuated down the system for 30 minutes. I charged the system and fired it up.

PROBLEM: I am running too high on the high side (275psi to 300psi) and too low on the low side (10 psi at idle and down to 0 at rpm)

I am running Duracool refrigerant (replaces R12). Ideal pressures with Duracool should be 24-28psi on the low side and 175psi on the high.

To say the least...... This car really has me frustrated!!! I have had it for 3 months doing a bunch of stuff to it. I want to see this thing go BYE-BYE!!!!!BIG TIME!!!!

ANY AND ALL HELP MUCH APPRECIATED!!
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