Well, tonight it finally occurred to me that I could go to the junk yard, and get all of the AC components from a '94 or newer, Corolla, and be able to buy refrigerant over the counter. I had been running R-90 in my '93 R-12 system, but don't really want to be doing that...
What all is needed to make this conversion? Or should I ask: Are there any components in common, between the '93 and '94 systems? I guess the compressor, lines/dryer, evap core, and condenser all need to be replaced? Beyond that, would there be any stumbling blocks which might trip me up?
I think you are making the problem harder than it needs to be.
You can use either refrigerant in either system, BUT the system needs to be clean since the two refrigerants and their lubricating oils arent compatible.
If your problem is JUST the clutch, replace it. If you have to remove the compressor to do it, then do a 134a conversion and a new receiver drier.
So are you saying that all of the components are the same between the two types of systems?
And how can one be sure that they've removed every last bit of the mineral oil from the R-12 application? Especially from the evaporater and condenser cores?
I know that if mineral oil mixes with the PAG oil used by R-134, that bad things will happen to the compressor. This is why I'd maybe be willing to switch all of the components out, although I don't think I'm too keen on pulling the dash to get to the evaperater.
I haven't personally tried this - but if you wanted to reduce the number of components to replace you might want to look into it: http://amzn.com/B004BSE69S
I haven't personally tried this - but if you wanted to reduce the number of components to replace you might want to look into it: http://amzn.com/B004BSE69S
I don't think it's that easy. Does the kit come with a vacuum pump and flushing rig, so as to properly prepare the system for R-134 compatibility and operation.
I'm not sure how to get EVERY BIT of mineral oil out, but I do know that it is indeed safe to convert an R12 system into an R134a. Just need new fittings. And of course proper tools and an evacuation machine, which is critical.
What year did Toyota switch over to R134a for these cars? My '94 has a hologram-type "R134a" sticker and the right fittings (no adapters).
Yeah, while R12 mineral oil isn't miscible with R134a, they don't have any adverse reactions to each other. Any remaining mineral oil remaining after vacuum suction is fine. Just add the right amount of R134a and PAG oil. Note that R134a has higher partial vapour-pressure than R12, so you only need 75-80% as much of it in the system to get to the proper operating pressures.
I haven't had any problems with the retro-fit kits. Just be meticulous with your procedure, rent/buy vacuum-pump & gauge-set and replace all seals/O-rings you can get to. Here's a nice summary of the process: http://griffiths.com/ac-system-help-introduction/r134a-vs-r12
When you take yours off and disassemble it, figuring out what failed may give you some idea if any shrapnel went into the system. There are flushing fluids you can use to rinse out the system.
Oh I'm an idiot. I thought you meant you thought 94 was the first 7th gen Corolla MADE, not the first with R-134a. I'm sorry!
Hey DannoXYZ, is this what your sticker looks like?
This is the factory R-134a sticker, the yellow one that says R-134a twice. Open the image in a new tab to see it bigger. I've seen it on many many Corollas. Not holographic.
This is the factory R-134a sticker, the yellow one that says R-134a twice. Open the image in a new tab to see it bigger. I've seen it on many many Corollas. Not holographic.
I know I'll get flack over this, but, over the past 20 years, I've switched from 12 to 134 probably a half dozen times, doing nothing more than swapping the fittings and recharging. Always has worked, and never had a failure. I can't say that they worked up to spec, but always kept me cool, and I live in the hot south.
On a side note, last year I bought an old commercial recharge/recycle machine. Been messing around with it, but still have a lot to learn.
Toyota put out a technical service bulletin for converting from R-12 to R134a. If the following link doesn't work in the future, just do a search for: Toyota R-12 AIR CONDITIONER SYSTEM RETROFIT pdf.
It will tell you how much R134a and oil to add, and what type of PAG oil and which seals/o-rings to replace. It specifically says there is no need to flush out the old mineral oil which I take to mean it won't damage the system to leave it in, but perhaps there would be a slight improvement if you did flush it since it does take up some volume.
So I wasted two hours this afternoon, and put the clutch pulley and bearing from my junkyard compressor onto the one on my car.
I had to beat the crap out of it with a hammer, to get it off of my car. The 'new' one came off its compressor easily, and went onto mine with just some light tapping necessary to get the snap-ring seated. It still had some charge in it, so I figured "what the hell," and grabbed my charging rig. I let that go for a few moments, until the compressor kicked on, but alas, it was making a horrible noise. So now I need to change out the whole compressor, and the clutch. Oh well, it was worth a try. At least the car is quiet now. I rolled around all winter with the clutch pulley bearing making a whirring noise. Maybe I'll get back on it tomorrow. But now I'm faced with finding something which can pull 30 pounds of vacuum. (MightyVac doesn't quite get it done.) Might as well do all O-rings too, while I'm in there...
New bearing makes no noise, but when the compressor kicks on, I'm getting a screachy grinding.
The junkyard pulley had a Nachi bearing. I was expecting a Koyo. I watched this vid on the youtube, and a Koyo was replaced by a Nachi.
Nice looking car he's got!
Is that a 5A-FE? Check out all of the additional room in the engine bay, and that carburetor-style air filter assembly!
So today I removed my original compressor and transferred the clutch and pulley/bearing back onto the new compressor.
Frickin' pollen! Makes my car look yellow!
Something missing down there...
Just checking to see if the clutch works:
I changed the O-rings on the hoses at the compressor, and up on those two junction blocks in front of the washer fluid reservoir.
Got it all back together, but my MightyVac is fubar, so I didn't get to pull a test vacuum. I guess I'll hit up vatozone tomorrow, and 'rent' another MightyVac, and return this one - I 'rented' it from them like four years ago...
You're going to be pumping by hand with the mighty vac for hours to pull vacuum on it. Get a junked fridge or window AC and make your own vacuum pump, you can use the outlet to charge an air compressor tank silently to boot!
I swear I pulled my '88 Mustang down to 28-29 lbs, in short order.
I can't get any vacuum out of the system with a different/good MightyVac! That made me question the seal(s). I also questioned my >20-year-old McParts R12-style connector.
Only way I could think of to test the seal was to just charge into the system until the compressor kicked on. As soon as that happened, I shut off my charging rig, disconnected it, and put the cap back on the charge valve.
I pushed the AC button several times over the next 5 hours, and the compressor kicked right on. I went out there roughly 10 hours after charging, and the compressor still kicked right on.
That sounds sealed/leak-free enough for me. AC season is only half the year here, but that AC-boosted defrost is damn nice in the winter...
I guess next, I should go to Harbor Fright, and get a gauge-and-manifold setup? Autozone loans out a real AC vacuum pump.
(Do as I type, not as I do...):facepalm:
The somewhat big two-hundo looms in my car's near-immediate future, and I'd like to observe (and photograph) that occurrence with cold air blowing in my face.
I told you it was single stage? I don't remember that... I don't know much about Toyota paints except that Super White is single stage. Every other paint color I'm completely unaware of clear coat.
Very nice job on the paint! The dark red was a single stage paint, never had clear coat. Probably good too, because there's no clear coat to peel and look ugly. We've had discussions on how best to do detailing, if you're interested I can relay what I learned from the fine people here. 94RollaDad has the same color Corolla and after a home detailing, his came out fabulous.
Oh wow I'm an idiot! My apologies, I don't know how I got that info. I think Scott and I were discussing it, since his car is single stage Super White, maybe he thought it. Maybe not.
I think there was a transition to low-VOC paints around the mid-'90s. A lot of the new formulations weren't that good. So if you had paint work done in the U.S., it may have had the "experimental" paints.
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