'86 420SEL: Converting back to R-12 - PeachParts Mercedes-Benz Forum

#1 05-16-2007, 04:35 PM

Or you could do the environmentally friendly, correct, cheap, and easy thing and just charge it with the very easily available R134 and suffer the oh-so-slight loss of performance. My car only takes 2 minutes more to cool off than it did before the switch and I definately havn't died of heat exhaustion yet.

I don't like to argue about things quite so dumb, but here's my on-topic advice. Don't bother switching back to R12 if the system works and has already been switched to R134a. It will save you problems and headaches later. Plus, why fix something that isn't broken?

gmercoleza · #2 05-16-2007, 05:33 PM

Quote:

Originally Posted by 15289577

...suffer the oh-so-slight loss of performance. My car only takes 2 minutes more to cool off than it did before the switch and I definately havn't died of heat exhaustion yet.

The original poster did not say where he was located, or perhaps I missed it. I see you are from Omaha, NE. Furthermore, you are new here. A tip for you: R134a vs. R12, conversion vs. no conversion vs. converting back to R12 etc. can stir very passionate debate at this forum. Just ask LarryBible! The consensus is that systems designed for R12 will work with R134a, but very poorly depending on where you're located.

I am in Texas, and I will tell you that the vent temps on my R12 car are a full 10 degrees colder than those of my professionally-converted R134a car. They also take about 5 to 10 minutes longer to get there, depending on how hot it is outside. In Omaha, where it may hit 95 degrees, that might not be a big thing, but here in DFW, when it can hit 115 in stop-and-go traffic, you need every degree you can get. If a system was designed for R12, it is going to be very difficult for it to cool as well without that refrigerant in there. Yes, I know expansion valve, P-flow condensor, etc. can be swapped in, but rarely will the performance ever be as good as if you just leave the R12 in there. Not to mention the cost of these parts and all the labor associated with changing them out - all for the price of a couple cans of R12 that can be had for $30.

This guy's situation is a little different, since he is considering converting back. I say go for it, as I eventually plan to convert my own R134a system back to R12.