While we are talking about oil, doesn't the RV-2 compressors have their own crankcase and the oil never leaves the compressor or enters the freon system?
Yes, the RV-2 differs from more modern compressors in that they have their own oil sump and oil pump that provides internal pressure lubrication. They are one of the most rugged A/C compressors ever put on a car. They make great off road air compressors. They do however circulate a small amount of oil in the refrigerant. I suspect this is to keep the compressor reed valves happy and the expansion and EPR valves moving. If you use one as an off road air source you will have some oil along with your air and need to keep the compressor sump filled with oil and check it regularly. About the only thing that will kill an RV-2 is no oil.
