How many oz of oil do I add to the compressor after pulling 29" of vacuum for 30mins?

Before you answer, here is the background so you see why I am asking.....

My original compressor died. I replaced it with a new AC Delco original style unit, I also replaced my orifice tube. I vacuumed the system, added oil, and charged it. After a week it stopped blowing cold. I found my leak as a bad washer seal on the back on the new compressor, even though it held vacuum. This was a year ago.

Fast forward to now. I have replaced my condenser, receiver/dryer, orifice tube, all o-rings, and am still using the replacement AC Delco compressor unit. I have not and don't plan on replacing my evaporator, it's too much trouble. BTW, we are taking about a system which has never seen anything other than R-12 and will be getting charged again with R-12 which I already have. My factory system holds 2.25lbs.

I'm going to a local AC shop to have them vacuum my new system to 29" for 30 minutes then I'm going to see if it holds for another 30mins. IF it does, exactly how much oil (oz) should I have them add to the system given my exact situation? I'm not sure how much would be left in the compressor after replacing everything since I know doing the vacuum won't draw out any oil. Does this old style compressor have an oil reservoir in it? Or was it disbursed throughout the entire system? My best guess is that I maybe have 2oz left in the system but that is just a wild *** guess. I thinking adding another 4oz? Again, a wild *** guess at this point.

Thanks! Alex

 

I found these thanks to CorvetteForum:

http://www.es-refrigerants.com/produ...true&Trying=ON

I order a 2 pack. I'm going to error on the side of caution and not add any oil yet since I don't know how much could be left in the compressor, evaporator, and lines. I'll get it working then test it, then add as needed.

 

I'd drain everything, flush it then add the 8oz required. The old oil should have been dispersed throughout the system.

The evaporator comes out pretty easily as does the compressor. Don't half-*** it.