Easy as pie! I went to Wal-Mart and bought a R-134 conversion kit for $33.00. The lit has 3 LBS R-134, 12oz oil, can tap, hose, and adapters to fit old R-12 systems. On my car, the system was nearly empty and was short cycling so I figured I needed it oil and R-134. The system uses 1.6 lbs of freon and ZAG oil. (The kit I bought advertises that it is compatiable with all oil types.) Located below the diagnostic port under the hood is the fitting for AC recharge. All that I did was connect the can to the hose, then the hose to the nipple under the diagnostic port, start engine with AC on and set to coldest setting, turn can upside down for liquid flow, open valve on can and wait till empty. Took <5 min for first can to go into system. You will hear the AC work as it builds pressure. The cycle time of the compressor on and off will get longer till it reaches its set point. Once the can was empty, kill the engine and close the valve to the can. Remove the hose from the AC nipple on car and finally replace the empty can with a new one. Repeat the first step till the can is about 1/2 empty, then place can upright for gas flow. Run this till empty or till the system stops taking freon. In my case, I did not use the oil since my evap. is leaking and I will have to recharge in a few months. When I go to recharge again, I will use some of the oil with freon.

This is not the perfect way of doing this, but it is cheap and effective. I did not use guages to verify pressure nor did I weigh the ammount of freon in the system. The AC blows cold as ice and the windows no longer fog like mad in my car in the rain. Given the condition of my AC system I figure it to be a waste to measure the freon as it is leaking out of the evap. anyhow. The cool part now is the fact that I can top off my AC for under $5.00 whenever I need to. That and I don't have to listen to a guy telling me that his dye and leak test will show a leak if I have one and that...yada yada yada. Oh yeah, and then cut him a check for 50 bucks.

Prospero