I swapped the R-12 in my old 230/8 for 134A and have no regrets, but I did the work with great trepidation because of all the stern warnings of disaster that confronted me. Many of those warning are now confronting you, too.

So, first the folklore...

Won't cool worth a damn: I have absolutely no concerns here, seems to be cold enough to store meat for a month, and a thermometer in the dash vent hovers around 34F when the days are hot. This is Montana, but it does get hot in the summer. Still, if you are in a hot humid place, then your results may be different.

Hoses will leak because 134A goes through them: Haven't found this to be true at all, and techs I have spoken with confirm that this was an initial concern but one that has not been supported by actual experience. Seems the old oil seals the pores of the hoses somewhat. Mine did leak at one end fitting on the compressor, so I cut the end and re-fitted the compression fitting and cured the leak. I also added a small amount of commercial AC system stop-leak as insurance, cost $4.

You'll have to change out...: the only things I changed were the dryer and compressor. The dryers are not compatible because the bag that holds the dessicant for r-12 will dissolve with r134a. Change the dryer to one with a green tag, which denotes the proper bag, which also can be used with r-12 if you chicken out and change back. The compressor was changed because I rebuilt it three times and it was time for a new one. Got a York clone and only regret not getting a genuine York, althought it works just fine. I did not flush the old oil, just made sure the new compressor was filled with ester oil which works with r-12 and 134a. Most of the old oil goes with the old compressor, but that which remains in the evaporator and condensor will eventually migrate to the lowest spot in the system, usually the condensor, where it sits without causing any apparent problems. Here's where I had a problem...my system has tapered copper washers that seal the fittings. These used to be common but new systems use O rings so they are now less common. I eventually got mine at NAPA, but they were special order. There are at least two sizes on our cars, one for the dryer and another for the condensor and compressor.

What else?...When you charge the new 134a it takes about 80% by weight of the original r12. This is true. Use a gauge set to monitor pressures for your vehicle, and use a vacuum pump to dry the system before charging and to check for leaks.

My system seems to work just fine and after two years has given no problems while cooling just fine. If all this seems way too simplified, bear in mind it reflects what is called the "simplified conversion" approach that is endorsed by USEPA. I was skeptical at the start, but after trying it I would not hesitate to do it again. Although, as some posts say, if you have access to r12 and don't mind the costs, keep it so the system can stay as originally designed. I chose to convert because I had no option but to pay $50-$80/pound for r12 plus installation costs of mega-bucks more. 134a is about $2 a can on sale at Wallyworld, so if it leaks a bit this year or next year, so what?

Anyway, that's what has worked for my old 114 sedan, maybe it will work for you. I'm sure there are many techs with different opinions and recommendations. Hope this helps and does not make your decision even more difficult.

230/8