I'm looking to convert my car from 134a back to r12... the 134a just isn't doing it for me.

Here's the plan:
Replace accumulator
Replace orifice
Replace condenser(if I can find one that is a step up)
Replace radiator fan (switch to dual fan set up)

I know how to do the labor. What I need to know is where to get parts from. I've found accumulators on year one so I guess I'll use those unless anyone knows where I can get one cheaper. So what I really need to know is if anyone has upgraded condensers or radiator fans with any great success and if so what parts did you use and where did you get them? Also.. where can I get an orifice tube and which one do I need for an r-12 system? And lastly I need to know about oil. Do I need to drain/flush the system or can I just replace the accumulator drop in some new r-12 compatable oil and be on my merry (ice cold) way?

Any advice is welcome, but I am not keeping the 134a and I'm not using a refrigerant other than r-12.

 

I usually just get parts from the local Autozone/Vatozone/Advance Auto Parts.

Can I ask why? Did you replace all of those parts when you converted to R134a in the first place? Putting R134 in a R12 system is the equivilent of putting ethanol in your gasoline engine. Results are bad.

I only ask cause your asking where to get parts. Since your asking, I'm assuming they weren't changed in the first place.
Since your willing to labor, I can offer the following advice for using R134:

1) The oils for R134 and R12 aren't compatible. Must flush out old oils before installing new ones. Compressor can probably get away with just draining out the old stuff, but a new one is good for peace of mind.
2) Your orifice tube needs to be different. The blue orifice tube from ford will drop right in and will work much better. They are in 84 ford thunderbirds.
3) A 4th gen condensor(a cross-flow type versus our older non-cross-flow). This will probably have the least effect, and could probably be skipped with little difference IMO.
4) The pressure switches must be calibrated differently. Sorry, I can't find the chart at this exact moment.

These things make a HUGE diffence, and will change your mind about the R-12 your gonna pay a small fortune for. If it leaks out, you've just thrown out a lot of money.

If your dead-set on your R12, just get factory-replacement parts for your vehicle, and pray you don't have a leak.

 

I switched my system to 134a and have not noticed any problems other than it doesn't seem to get as cooled. But, that maybe do to the underdrive pulleys. I didn't even change out the compresser oil, or any of the seals. its been that way for two years now with no problems.

 

As long as the compressor still cycles on and off, the pulleys won't have any effect because the cycling is controlled by the pressure switches. If you haven't recalibrated these switches to R134 specs, that would be one of the reasons your not satisfied with it.

If everything is still holding together, I'd try lowering the low-side pressure(via adjusting the switch) by 4-6 psi to see if that helps. Around 28-32 psi to switch on the compressor seems to work well. It's free and it cant hurt.

 

Someone converted my 86 to 134 and didnt change anything, when i got it it didnt blow very cold, i found out they converted it all wrong, so i recently replace everything even the condensor and compressor. 134 is in it now and its ice cold!

 

I don't think any of the parts were converted we the previous owner put 134 in. Not sure but since he did not even change the service fittings on the system then I am going to assume he did nothing. I've never had good luck with 134 conversions so I'm sticking with r12. I have a large supply of it.... enough to charge it every summer for the rest of the time I have the car so that's not an issue.