JoeWinkie

The original a/c compressor in my RX-7 failed shortly after I bought the car... the pulley started making this ungodly machenical ear-piercing continuous scraping noise. My mechanic cut the belt because I couldn't afford his $800 price tag for a new system. Well, a friend of mine had an a/c system that he pulled from another rx-7 that he says is in good shape, and gave it to me. Now I want to stick my "new" one in and pull the bad one out. Thing is, what do I need to know before I start doing this? What do I need to look for? He gave me the tubing, condensor thing (looks like a littler radiator), and compressor, and I want to know how I can minimize my cost to do this, if there's anything I can do myself, what the deal is with moisture, and how can I be sure the new system will even function properly without just taking a huge financial risk? I would love to hear from anyone who can clue me in on this. Thanks!

Joe

CrackHeadMel

iTrader: (2)

i pulled my ac, i know pulling and installing are different,

but i can assure you that the hardest thing is probly going to be putting the compressor on, and when putting the condensor on, if you take that underbelly plastic thing off, Unbolt the oil color from its mounts you can push it out of the way and wedge the condensor into place

SpeedRacer

There are 4 12mm(or mabe 14mm)bolts that hold on the AC compressor. Two on top and two underneath. The too underneath are kinda hard to get to cause you can't see them. Just stick your hand under the AC compressor and feel them out, shouldn't be too much of problem. I removed my AC probably almost 2 years ago so I don't remember exactly what all connected to the AC compressor.

You probably don't need to replace the whole AC system. Sounds like just the compressor went bad. So just replace the compressor first, keep the stock evaporator, condesor, and tubing. Just look at the old compressor before removing it to see where the lines should connect to the new compressor. After replacing the compressor, if the AC still doesn't work or get cold, just have it recharged with new refrigerant, or whatever. The condensor and tubing don't really go bad, unless the fittings on it are no longer keeping a seal, in which case you'd have leaked freon(sp?) into the atmosphere creating a hole in the ozone above your car wherever you drove.

Felix Wankel

You need to have the freon evacuated before you swap compressors. Then have a vacuum pulled on the system after you swap the compressor in, to be sure that its in good shape. Then have it recharged.

(You could just let the freon out into that atmosphere, but this is bad, and also very, very illegal)...

SpeedRacer

Ok, I am not POSTIVE of this, but I'm pretty sure you can remove the AC compressor without discharging the freon. I seem to remember removing the AC compressor first when I removed my AC. It wasn't until I removed the lines from the reservoir that the Freon was discharged(I was told from the seller that it had already been discharged so don't flame me). It scared the ***** outta me as green goo came flying out and got all over my hands and arms, I shut my eyes and held my breath and ran about 10 steps away before opening my eyes. Anyways, I don't think the freon lines actually run to the compressor, I thought the compressor was just to force air into the AC system to circulate the freon through the system, I don't see why the freon would actually need to flow to the compressor. But once again it was almost 2 years ago that I removed my AC, so I can't be sure.

Jodoolin

Did mine last week. Simply took chance with one I took from bone yard. Since only the compressor was shot, I saw no need to replace anything else.

However, the 89+ series came with two different compressors. Nippondenso and the Sanden. The high/low lines into/out of the compressors are different. Same swap easy. A mix will be a problem. The pressure switches are also different I think. If it is not an equal swap, you will have to change the lines and electrical feeds. Lot of work when a same type switch will take about 1/2 hour.

Once switched I took mine to a Mazda dealer, had them vacuum the system and charge with R12 refrigerant. Cost 175.00 in Michigan which was reasonable compared to much higher quotes other places. Do not simply charge yourself with the do it yourself kits. It is my understanding that the mineral oil lubricant used in R12 fluids is not compatible with the new stuff. Oh, ya, don't forget to chech the compressor oil level before you install the replacement used one.

Good luck

JoeWinkie

This is good info so far... but I still need to know what the deal is with not letting moisture into the system, and how to accomplish that. And I also read somewhere that if the compressor had undergone mechanical failure and had metal scraping on metal inside it, that it was possible there were metal particles in the system and that could riun the new compressor. Any input on this???

Felix Wankel

Thats the point of the vacuum.

Jodoolin

Good question. I will tell what I understand and let the chemically astute folks on the forum post the chemical reactions.

The wax free mineral oil lubricant used in R12 A/C compressors will break down when exposed to water vapor and air. Ergo: blown compressor/seals/etc and right back to where you are now. Also, for reason I am not sure of, water vapor and freon also undergoes an undesirable chemical reaction which can neuter
( Hehehe) the freon.

Anyway, its always best to vacuum/purge the system of water/air regardless of which refrigerant you are gonna use. Besides, when you capture the vacuum "stuff, as certified shops do, you are helping to protect the environment we all share.

Jerry

JoeWinkie

Ok, so apparently moisture is a BAD thing to have in the a/c system. Are you saying that if my new used system that was given to me has any pipes open to the air that I'm screwed, or can the air be dehumidifed somehow before putting the refrigerent in? I'm starting to get the feeling that I shouldn't touch any of this stuff myself for fear that Murphy will rear his ugly head.... It seems liks it gonna be either horrendous to do or horrendous to pay someone else to do. Damn, all I want is to not sweat.

SpeedRacer

I hate that damn Murphy and his friggin law...I say replace the just the compressor for now, leave the belt off so it's not turning the compressor wheel. Take your car into a certified shop that does AC, have them do their vacuum deal, and recharge your system with freon. That should probably do it for you.

Jodoolin

Ditto on Speedracer. You put the thing in and a certified shop charges. They will also do pressure check and find/fix leaks if any. So, for a little over 100 you don't have to sweat!

Jodoolin

By the way, you can put the belt on. Just don't turn the A/C on. The clutch only engages when you turn the A/C on. The internals will not be working otherwise only the pully and belt mount will be spinning.

Thaniel

Been there done that. If the compresser broke and put metal in the lines you HAVE TO have it cleaned out. I put on a brand new compressor and reciever dryer after the old one quit and it lasted only 1 month (replaced the compresser and had a local shop vac and recharge the system). That's when I gave up and took the thing to the dealer and had them do the whole thing. (another new compresser and reciever dryer and they cleaned out all the metal shavings) Trying to save some $ by doing it myself didn't work.

You will want a new Reciever dryer. There is material in there that absorbs water. Obviously don't put a newone on until you are going to have vac pulled on it or any humidity in the lines will saturate the material.

akageals

I removed all the A/C from my car, flushed it all out with brake cleaner, reinstalled it, vac. it out with an old refrigerator compressor, and then refilled it with R134. The A/C works great and the complete retrofit cost less than $100.00 . Not that hard to do. The parts don't even have to be removed...just opened up and flushed with the cleaner.

Todd

JoeWinkie

This forum thing rocks, you guys have given me a lot of good information that I doubt I'd have been able to find otherwise. So here's what I'm gathering so far: I need to have my current bad a/c system discharged so as not to break any laws and **** off the enviro-*****. Then I need to remove the bad compressor. Then I need to have the compressor-less system treated/flushed/whatever to eliminate any metal shavings. Then I need to install my new compressor. Then I need to have a mechanic do a vacuum test and to A) remove any extraneous gas and moisture so as to avoid forming hydrochloric acid which is BAD for metal, and B) verify that the system CAN hold a vacuum and has no leaks (Thank you Speedracer!). Then I need to have the system recharged with R12. Then I need to install the belt for the pulley. Then I need to push the A/C button in my car and finally cool myself off. This is what I've gathered from what you guys here have told me and what I've read/heard from other sources. One or two thing though that I *think* I'm not quite sure on... Isn't there a certain amount/type of oil that's supposed to go into the compressor and other parts before going active? And at what point do I put the new receiver/drier in? If I'm mistaken on anything or have anything in the wrong order, please someone let me know! And if anyone by chance happens to have any photos if such an operation as I want to undertake, or has a digital camera and can take any appropriate pictures, I'd really appreciate it. Thanks guys!

SpeedRacer

I wish my car and removed AC components were here with me in Canada, then I'd take pics for you. Actually, hell if I was back home, I'd just get you address and come over and help you do everything.(I am also from Portland Oregon)

Anyways, I'm not an AC expert by ANY means, but If I were you, I'd just take off the old compressor, put the new one on(and apparently the belt too, as long as you don't turn the AC on). Then take your car to a certified AC place, and tell them what your deal is, and they should vaccum the line and do a pressure test for leaks.

Can anybody else verify whether or not it is possible to remove the compressor without depressurizing the AC? I seem to remember doing so.

Thaniel

Not possible. The compresser pumps FREON. Remove one of the lines and freon everywhere.

You can remove the AC compressor from the engine (as long as you don't remove or break a line) without discharging the freon.

BTW. MY old 200sx busted a line to the compressor and it fumed spectacularly for what seemed like 10 min.