Just wondering if anyone has done a conversion on their ac system from the R12 to the new stuff (R34?)? Just kind of wondering what parts could be swapped and the procedure to make this work? I'm sure someone has thought of it or tried it somewhere. I have to have my AC fixed on my 1990 200TQ, and wondering if the money I spend (~$350) will be worth it, or would it be better to spend that on parts for a conversion? Just looking at the options.
I had the conversion to 134a done on my former 1990 80q. There's a few seals they need to be changed in a few places (around the condenser if I remember right) due to the different oil used for the 134a systems. There's also different fittings installed that are specific to 134a (so that R12 isn't put in accidently). On my 80q I used all stock parts.
I know on some of the older cars the compressors (Nippo I think?) don't like the 134a. It worked great on my car for 3 years (until it was totaled) with my stock, non-problematic, compressor. I would think your '90 would use an okay compressor but I'm not certain.
Also, I've recently heard that there's some new freon out that doesn't require any changing of seals. I can't remember the number but it's worth looking into.
I'm doing a conversion to Freeze 12 on my 1989 80 Quattro. I just had the mechanic evacuate the R12 and do a leak test. You just have to change the fittings on the service ports and get the old freon drained. Freeze 12 is completely compatible with the R12 oil and you don't have to open up the system if there's no leaks. There's kits on ebay for $55 that have everything you need, including 3 cans of freon, it's so much cheaper than R12. Definitely the way to go once it's time for a recharge.
Accidentally I have come across this site and here it share the details regarding the AC conversion possibility. The details additional resources provided here was really useful for me because i am planning to change my old AC. Please share more update on that.