GM A-6 A/C front compressor seal leaks???

[njsteve]

I have just replaced the a/c compressor in my Z11 for the forth time. Each one seems to seep oil from the front clutch seal and leave an annoying mist pattern on the fenderwell and the hood insulation. Do they all do this? I have replaced 2 rebuilt units, then a brand-new GM AC-Delco unit, now an AC-Delco remanufactered unit. The worst of the bunch was the brand new one. The system is running R12 (very expensive stuff these days) and all the pressures are within spec. The evacuated system will hold vaccuum for hours: there are no leaks anywhere. Has anyone else run into this problem or am I just too finicky???