Thanks for the quick replies fellows, I will stick with R 12.

The $40. per can price quote + tax was at O'Reilly Auto Parts. I just bought two 12 oz. cans on eBay for $48.50 plus shipping.

The one owner ( based on a Car Fax report ) 1984 380 SL recently purchased I have reason to believe has not been used since 2000 as the latest Missouri inspection sticker on it is 1999. It came from a RV dealer friend of mine who took it in trade on an RV from a person across the state in St. Louis.

The system has some charge in it now and I can jump the low pressure switch to activate the compressor clutch so I doubt there is any air in the system. It has 2 Schrader valves on the suction line ( anyone know why and which one do you use to charge it ) and one of them does not have a cap on it. Between that and the plastic lines I just want to guess that time took its toll with leakage. Fortunately I still have a set of Gauges and a can tap although auto AC was not ever my strong suit.

I totally enjoy this forum and the wealth of knowledge available. I will be here quite often and the search feature is great. It was a great idea to put that sticky note on the top about it.

Best Wishes,
John