replacing heater core-should I do R134? (+write-up) (1 Viewer)

[60 toy ota]

Consider recharging with propane rather than R134a.. mine's been running propane (well, a commercially available product called Hychill in Australia which is mostly just propane) for about a year now. No issues and a simple recharge with no system changes.

That sounds a bit scary in the event of an accident, or even just a leak and spark in the right place, no?

 

[rustybucket]

I've finally been bitten with a leaking heater core. I'm ready to dig in and probably (hopefully) have a good radiator shop fix it. There's good info on the job though no videos, If i feel like the community would benefit from one I may go ahead and do that. This thread is a write-up for the disassembly of the dash, in addition to the following:

"while I'm in there", I'm thinking of converting my A/C (which has been inop for 10+ years) to R134a. I don't know much about why it doesn't work other than when I jump the compressor clutch the air temp hardly changes. I don't want to try to source R12 only to find I can't hold it.

MODS: It seems that there's a lot of diverse opinions on weather or not the retrofit is a good idea, and how to go about it. Being that there's nothing in the FAQ's about this, My goal for this thread is to come to a consensus on how (and even when) the conversion should be done, So I hope to hear from the experts.
Assuming my system can't hold pressure, I think it's fair to say the conversion is the smart (and legal) way to go. So far it seems like I'll need to replace the following for best results:
-all 0-rings
-drier
-retrofit valve fittings for R13a
-what about the expansion valve? Is this a common wear item?

From there, the procedure seems to look something like:
-drain the system: use the jumped compressor to empty out the opened system; remove compressor and drip drain the rest
-add oil to drier and replace all the aforementioned hardware
-evacuate (apply vacuum to) the sealed system
-add new R134a freon.

If someone could chime in and confirm that I my thinking is correct to this point, we'll move on to the specifics.

Does anybody have experience with these rigs not holding pressure due to anything besides the old O-rings?

Drew

R12 has been banned for a very very very long time. R134a was it replacement because it doesn't deplete the ozone layer. The molecule of the 134a is much smaller than R12 so you can't use the same seals as the R12. R134a will leak out of the seals. So you have to have new seals that will prevent R134a from leaking out of them.

 

[rustybucket]

That sounds a bit scary in the event of an accident, or even just a leak and spark in the right place, no?

Yes I could be but just imagine if all the propane let loose it would look like flamethrowers coming out the side edges of the hood LOL