Hey everyone. I have a 1991 LS400 and I just got a bunch of work done to it like replacing timing belt and water pump and valve cover gaskets spark plugs and wires and a few small other things. The AC in my car doesn't work and I think it's just low on Freon as it hasn't been charged in 20 years. Is recharging the AC something I can do myself? I live in California and was told that you can't buy our 12 freon anymore. I have seen it for sale on eBay. My question is if do I need to flush my system before I put new freon in there? Or can I just go ahead and put new freon in? Does anybody know of any tutorials out there?

Thanks in advance

 

I suppose you could buy some and have it shipped in... but I'm not sure of the legality of doing that in California. Do they test for it with CARB? If you can't buy more of the refrigerant you have in your system (R12) then your only choice is to convert the system. Do not mix refrigerants.

I don't know whether you can just swap refrigerants and call it good for like 4 bucks, or, if you need to completely replace all of the hardware (compressor, o-rings, etc). You'll find people on the internets saying both.

 

I haven't heard of CARB. Is that the same thing as a smog check?

 

What does, "doesn't work" mean? No cold air? Doesn't blow air at all?

There are a lot of reasons why an AC system doesn't work. Determining why and performing required repairs can get costly...fast. Since the system hasn't worked for 20 years, I would pay to get a system assessment done from an AC repair place. This way you'd be better informed as to which direction to go - repair and recharge with R12 or convert to R134.

Things to consider:

• AC system are closed systems. If there's leaks, the system is no longer closed. R12 mixing with air (moisture) creates corrosive compounds that have been circulating in the system. This compromises the components.
• Regardless of the cause for "doesn't work", repairs will consist of component replacement.
• The system needs to be "opened" in order to replace components. If the system is open, it's better to just proceed with conversion to R134.
• Conversion entails removal and flushing of the R12 compatible refrigerant oil (mineral-based) from the entire system and replacing it with R134 compatible PAG (polyalkylene glycol) refrigerant oil.
• Both refrigerant oils can exist in an R134 system; the different oils don't mix. The mineral based oil will just settle in the system. I've done conversions this way but I'm still "iffy" about it. If the system is opened for component replacement, I feel it's better to remove (and flush) all the old oil.
• Have a FAT wallet.

IMO, AC work isn't really a DIY proposition, regardless of the recharge kits and refrigerant that's currently on the market. I do my own AC work but I've invested (in retrospect, rather foolishly) in the minimum equipment needed to do this work.

 

California Air Resources Board; they handle anything and everything related to emissions yes. They aren't actually the ones doing the checking, but they set the high-level emission rules. I don't know the specifics of how it's tracked, I just know it's a thing.

& thanks for replying Paulo - that is a far more informative post than what I was able to cobble together.

 

awesome response. thanks! i agree it's best to convert to R134. even if you find a can of R12, getting it to adapt to the fittings will be your next challenge as they differ. part of the R134 conversion is an adapter.

 

Thanks for the replies guys! My AC doesn't blow cold air at all. It moves a lot of air and everything else works, it's just not cold.

I've looked online and I can't seem to find any R12 for sale, so maybe I will have to do the conversion...

I think I will bring it to a shop to have it assessed.