R-134A retrofit time

I know this has been discussed, but the serach gave me nothing.

The R-12 system in my 86 Nissan truck has all but crapped out the past few days. I've been looking at taking the leap and homeschooling a R-134A conversion. I do not know for a fact that the compressor blew, I think its just low on refrigerant. Is it necessary to remove the compressor and physically empty the old oil? I understand you can't really clean the old condenser, so that, the drier and expansion valve would be replaced. Anybody know how hard the expansion valves are to get to. I was looking at replacing the hard parts with those from the later hardbody trucks that had the R-134A systems installed to hopefully make the system more efficient. Anybody know if its plug and play or am I going to have problems?

BTW, dispite what shops will tell you, it looks like it is not illegal (according to the EPA) to add R-12 to a system without leak checking it first. If you are going to repair it, then you must evacuate and follow the rules.

I know very little about AC systems.....

BUT!

I did talk to a guy who filled his AC system with propane on a mid 80's audi instead of r12. I'm not sure how I feel about that idea but his reasoning was propane works as refrigerant very similar to r12, enough that he didn't have to change the system.

rcutclif wrote: I know very little about AC systems..... BUT! I did talk to a guy who filled his AC system with propane on a mid 80's audi instead of r12. I'm not sure how I feel about that idea but his reasoning was propane works as refrigerant very similar to r12, enough that he didn't have to change the system.

In the US you can buy cans of R134a at parts stores. In Canada we can't, and have to buy "alternative" kits. Most of them are just propane as far as I have read. They do have different kits for R12, R22 and R134a though, so there may be slight differences. That being said, not sure how you'd get propane into your system other than buying one of those kits.

some of the volvo guys have done the propane thing... apparently it works very well, similar to r12 vs the r134a (r12 was more efficient from what I understand and run better/cooler than 134 on the same system)

the one think I know a number of guys ran into was figuring out how much propane to use... too much and it would freeze up the system.

Just buy more r12. The demand is pretty low now. It's all over craigslist for around $20/can

old_ wrote: Just buy more r12. The demand is pretty low now. It's all over craigslist for around $20/can

Didn't think about Craiglist. It is on Ebay, but the price is all over the place. Unless I can pass the EPA 609 test though, I can only buy it to resell to a certified mechanic. I'm not sure I could find someone to put just it in.

I called a local indy shop to see if they would ad R-12. They want $275-300 to convert to Freeze 12.

I'd do a dye injection, vacuum it down and fill it with one of the hydrocarbon R12 substitutes available, go from there. AC becomes much less of an expensive luxury and more of a given once you've got all the equipment and know how to do it yourself.

I had to replace the compressor on an R-12 car (the magnetic clutch was broken and the difference in cost between the clutch and a whole compressor wasn't much). I replaced the compressor and the receiver dryer since the system had been open for who knows how long before I bought/rescued it. I decided that since the car was low end, I just vacuumed it out and recharged with 134a and didn't worry about doing it perfect and the oil incompatibility, etc. Old cars are pretty durable....

Blew cold for the next 18 months until I sold it.

I've converted two systems. On both I replaced nothing. I vacuumed, and filled with R134. They were both working when the cars were sold or scrapped.

I might also know someone that has a "hydrocarbon alternative" made by Coleman in a R-22 system that cools his shop better than R-22 ever did. My truck has a R-12 system that will probably be converted to a alternative when it has a problem.

In reply to glueguy:

Assuming you charged the new compressor and drier with ester oil(mixes with the R12 mineral oil, compatible with both 134 and 12), thats an acceptable long tern conversion.

My '86 Supra had lost its original R12 charge years ago. It has been blowing cold for two months now by doing nothing other than adding R134 fittings, pulling a vacuum, and charging the system with an ester/134 mix commonly sold at Wal-Mart. Seems to have worked for glueguy and Toyoman as well, so give it a shot!

Kenny_McCormic wrote: In reply to glueguy: Assuming you charged the new compressor and drier with ester oil(mixes with the R12 mineral oil, compatible with both 134 and 12), thats an acceptable long tern conversion.

That's what I did. There is a lot of internet doom and gloom out there about incompatibilities, etc. My point was that if it was a "nice" car I might be more inclined to be thorough and do it "right," but for a typical GRM car I wouldn't worry too much about it.

R12 or alternatives are readily available. Look at car shows and automotive type flea markets. Yes, you are legally required to be certified to use R12, but only Ebay forces the issue.

Sure, you can do the conversion to R134, many of us have done it numerous times, without incident. But if all you need is a can of R12 every year, why bother?

foxtrapper wrote: R12 or alternatives are readily available. Look at car shows and automotive type flea markets. Yes, you are legally required to be certified to use R12, but only Ebay forces the issue. Sure, you can do the conversion to R134, many of us have done it numerous times, without incident. But if all you need is a can of R12 every year, why bother?

The problem is finding a certified person who will install the R-12 without upselling me. I've had trouble finding anyone who will remove my R-12 and keep it. The system isn't empty otherwise we would not be having this discussion.

To get R-12 off eBay, you must be certified or sign a statement that you will resell to a certified person. I found some R-12 on Craigslist without any mention of paperwork etc. Would EPA show up on my doorstep?

HF still sells the manifold set for R12. You can find used filler kits (short hose & tank connector) on ebay and flea markets.

EPA is not chasing down individual users of R12. Go into business and perhaps.