My AC system is void of coolant do to engine repairs. I want to recharge it, but it is outfitted with the old R-12 system. I have found converter kits that change over the connectors and coolant to the newer R-13(?)freon. Is this the way to go? Does anybody no how to do it? And whats the best way to make sure that the old coolant is totally gone? Thanks.

 

Unfortunately you're going to get screwed on this deal...

yes, you DO need to convert to the R-134a refrigerant system. I forget how much the kits are, but you said you already found one.

the best thing to do is just take it to an A/C repair shop and have them take care of it. there is so much legal BS with freon and refrigerants that you can't do anything to it anyway. Believe it or not, it's actually illegal for you to even touch the A/C system if you don't have a liscense.

Sooo, you're just going to have to take it in and pay them what they ask. sucks, don't it?

As for how they get all the old stuff out, they'll clean the system somehow and then they put a vacuum pump on it and suck everything out.. then recharge it with new stuff.

 

I don't know if you need a license to work on your own car, but to buy R12 you do. I see the new stuff on the shelf of the autoparts store, so I don't think you need a license for it -- but call your store to check. The license is really easy to get. I have an old one and it seems like they were more interested in collected the fee than anything else. A mick test and they send a id card and certificate.

The old R12 seals are not very resistant to the new R-134?, so you have to change the o ring seals. You won't be able to change some of the seals like the shaft of the compressor. But do change all the other seals -- each connector at the evaportor, condensor, collector/drier, etc. You also should change the oil to the synthetic that required for the new type of freon, you have to have the proper oil for the specific freon used -- see instruction with the kit. That will involve flushing the system, another hard thing to do. Since all the freon has already escaped, there should only be a trace amount left in the oil. After changing the seals, the drier and filter - screen (the latter two are optional but I would do it if the price is low), pressure test it with dry nitrogen or argon. DO NOT USE AIR or you may have an explosion! I usually disconnect the compressor clutch wire for safety and see it it hold 100 psi for 48 hours. Then I vacuum, it to 50 to 100 mTorrs for 4 hours to remove any gas and moisture. Then put in the freon. What I do is an overkill, but I don't want to waste any freon, esp. R12. R-12 was about $50 per Ibs. last time I looked. When I replace the evaporator, I stayed with R12, but that's a personal choice of all the labor involved and that car had a poorly designed AC system and small compressor (an 84 300TD), but my 93 Nissan has plenty of cooling with R134.

!!!! DO NOT PRESSURE TEST WITH AIR !!!!!

USE SAFETY GLASSES AND FREON IS EXTREMELY COLD WHEN RELEASED.

 

There is a company that sells very simple conversion kits for about $35 (http://www.id-usa.com). Since your system is empty, all you would have to do is change the fittings, put in the oil and the R-134. Now I know the receiver drier should be changed and the system vacuumed, seals changed, etc., but right now getting the AC working for a few buck may be worth it to you. I know I picked up a kit and spare cans of R-134 in anticipation of the day when the CA goes out in my wife's 88. If you do this conversion, it would be a good idea to stock up on extra cans of R-134, since I've read that many states are considering making it a law to have a license to buy R-134 in the future.