Most of the work is very easy, although time consuming. Diesel Giant has a write up that will cover you for the cleaning. Have a professional on tap for the evacuating, charging, and such. My local AutoZone loaned me a flush gun, I bought the flushing oil for cheap from them. Make sure that the flush oil is compatible with your new refrigerant (R12). Lots of time and compressed air will get the entire system clean(no more green stuff), just have a new set of o rings, and filter ready. I broke the temp sensor when installing, and had to buy another, got a new pressure sensor while I was at it.

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Mercury is a boxer

1984 300d
1999 Prelude
Medici road bike
Klein touring bike
Klein mtn bike