Ac compressor squeal?

[sleepertruck72]

Did the compressor come with oil type and "balancing" instructions ? The compressor can have too much oil and incorrect oil also. How long did you vacuum the system before charging refrigerant ? I would Try a laser if available to check pulley alignment for the belt squeal, but I would not tighten as tight as described. I would drain the compressor and add the oil spec indicated for the compressor. It may have too much oil. Since you wired the clutch, I would take off the belt, turn the clutch on and see how difficult it is to turn by hand. You should be able to turn it without too much extreme effort. Is it an orifice tube ? Is it the same orifice for R134a vs. R12 ?..it sounds to me like a bad A/C compressor...but that's just my .02 cents...