Well summer is almost upon us and it is starting to warm up here in Mississippi. My 71 chevelle had a usable, but not working a/c on it when i bought it. I have everything to make it work but just need to know how. I took off the compressor and lines for it but have everything still. Now i need to know how to drain it, charge it, and make it work. I heard you can use sythetic oil and some kind of flush and run r-134a or w/e. Is this true? Help me get my a/c working with little or no costs please.

you can hook everything up. make sure you have a good compressor. if it was me, i'd see about a new drier/evaporator. a new compressor's warranty requires that you replace some lines and another part i can't recall right now.... then you retro fit to r134, (kit at walmat, the 'zone, oriellys) get you several cans of refrigerant and an oil charge. take it to a shop you trust, have them hook it upon their machine, evacuate it for at least an hour, two if the shop has the time....then charge it up. if you had good parts, it ought to work.

Well see the thing is, is that the copressor is 33 years old and i think it lost charge or w/e. I was wondering if i could flush the compressor and like refill it with r-134a or something? Like is that possible or do you think i need new stuff. Like i dont know what a drier/evaporator is so if you like could explain it that would be cool. I dont know much about all this stuff.

a 33 y/o comp. is most likely shot. if the lines have been open anytime at all, they are most likely shot too. you'd be time and $$$ ahead to go ahead and get new parts. or at least newer....

will the compressor spin over? does the clutch engage? how about disengage? you can get a new clutch assembly if the compressor is ok . but at the price the gas is gonna cost, and having to have the system evacuated for charging, i'd (if it were me) replace anything that might not be up to snuff.

how long has the comp. been off the car?

Well i took it off prolly almost a year ago, at that time it seemed to spin ok and all. I dont know how to tell if the clutch engages? What gas? I dont know what having it evacuated for charging is? As you can see i dont knw a lot. If i did have to get new stuff how much is it?

gas = r134a refrigerant

i don't know if there is a way to tell if the compressor is engaging without it being installed and having power to it.

call autozone or oreillys, ask how much for a new compressor for your car. then they will tell you what else you will need to replace to keep the new compressor under warranty. (they won't warranty one unless you replace certain components. which halfass makes sense.) that'll give you a ball park guesstimate of parts price......

whenever you open an ac system to the outside environment, you introduce impurities and other crap into the system. the ac shop will hook up to the system and put a vacuum on it to 'evacuate' all the gasses in the lines. the longer it's being sucked clean, the better. duh..... the equipment to do that is hi$$$ , pay a shop to do it. unless you got a buddy.... after the system has been under vacuum for at least an hour, i like to go two if the guy isn't too busy, then you connect to the lo side, pop a can of oil, and allow the system to 'charge' ......


for the year that the compressor has been off, all kinds of 'stuff' have been exposed to the sterile confines of the ac system. the drier, which removes humidity from the lines, has been soaking up any moisture it could, and is most likely shot.

so what i think i'm trying to say, save up the money and do it right, cos if you put a new compressor on, and nothing else, i guarantee it won't work long if at all.......

Does that car still have the old style GM 6 cyl compressor on it (The black one)? What the "experts" say is that the old cast iron compressors are not compatible with the 134 refrigerants and oils. Of course "they" said a lot of things in the beginning of the phaseout that the oils were not compatible and would coagulate and blow up your compressor if it wasn't completely drained and flushed of all old oil. I do prefer to see anyone changing over the system to use the new style aluminum rotary compressors. What the industry has found is that you can just add new oil (preferably what the factory recommends) or just add 6 oz PAG oil (R134a compatible oil) to your system if your using the late style compressor. Evacuate and recharge like crazy larry says. You will have about 2 to 4 degrees higher temp at the outlet because r134a doesn't have the heat transfer capabilities the r12 has. The r134 system generally uses a bigger condenser to remove the heat from the compressed freon. Also a different expansion valve or orifice. If you do convert your original system without changing the compressor you could end up destroying the compressor with catastrophic results contaminating the complete system with fine particles of your compressor, rendering your whole system irrepairable.
Hot in Mississipppi? 96 today and 98 tomorrow here in California ........but its a dry heat. I already got my A/C serviced in my cars!

Anybody use Freeze-12? It is safer than R-12 and is compatible with R-12 and R-12 systems. That's what I've herd anyway.