Restore AC system to R12?

[Mustang Munkey]

Dear Friends, I bought my 1989 ASC McLaren Mustang in September of 16 from a friend of mine. I knew when I bought the car that the AC had not worked since he bought it in 2008. I took it to a shop last week and asked them to diagnose my AC system and tell me why it was not working. They said it appeared that the system should work if it were charged. I asked them to charge it, they did and it worked beautifully for about a week. This week no cold air at all. I went back just like they asked me to do in the event that the ac stopped working and they used a black light to find the die they put in the system to determine where the problems were. They showed me a leak in my condenser and in the compressor. I have replaced the AC system on a 2004 toyota minivan and did the work myself so I am leaning towards tackling this job myself as well. However, it is clear to me that someone has added the fittings to my AC lines to allow it to accept the newer 134a coolant but it does not look like they did a full and proper conversion to the system. I am thinking that since it appears that I am going to have to replace the condenser and the compressor I might as well convert it back to the original R12 system. Have any of you done something like this on your ascmclaren? and would you have any words of advice to share with me on a project such as this? Any advice or suggestions made with the intent to be helpful would be greatly appreciated. thank you, Mark

[bigzeke42]

The R12 cost a lot more than R134.

[svo413]

If yours is already converted then I would stay with the 134. If you were replacing most of the system then maybe go back to r12. R12 is not cheap but if you add the cost of conversion to r134 it's not so expensive to stay r12.

The shop should have never filled your system without leak checking it. Flushing the system is required when going to r134 so I would imaging the same going back. Be sure to change all of the seals regardless which way you go. The hardest part for the dyi is the pump out the system after servicing it.

There is not much to converting to r134, flush, add correct oil, add fittings, pump out and leak test, add Freon. Any new components should come with upgraded seals unless you have an odd ball unit like used on the 4 cylinder..