hiluxhack

So I've got a 94 hilux, 22re with what I believe is low refrigerant. The low side line has an r12 schrader valve but the high side line has a permanent ( not screw in type) 134a fitting. WTH? I know some trucks in that transition year came with 134a but I've never seen one with some parts of each. Is there a way to identify the type of refr. in a system? Should I call a priest? Shaman? Witch doctor? Back in the dark ages when I got my certification, you weren't expected to really know anything accept not to vent to the atmosphere. Suggestions please.

millball

The truck should once have had a sticker under the hood or near the radiator header that told the type and amount of refrigerant needed. I guess many of these stickers have dissapeared over the years.

I found this. A bit pricy:

http://www.instrumart.com/products/3...t-gas-analyzer

Most '94s' should have been factory equipped with R134, but I've heard that a few early production '94s' did use R12. (I've never seen one)

Maybe repairs have been done to your AC that mismatched R12 and R134 type components.

Your most practical solution may be to flush the existing oil out and recharge with R134 and new oil charge.

scope103

Come on by and take a look. My '94 has a production date of 9308, and so came with R12. Toyota apparently took the full count and didn't switch to R134a until January 1, 1994.

Obviously, if you have mixed connectors someone did an "upgrade" and screwed it up completely. I'm guessing the liquid line failed (high side) and was replaced with a "modern" version. Did they replace the R12 or go with R134a? Who knows?

I think that just adding either refrigerant is asking for trouble. (They don't get along with each other.) If it were mine, I'd vacuum it down and fill it with R134a. The good news is that Toyota doesn't think you HAVE to flush out the old oil. http://tms.ccar-greenlink.org/NewsLetter/ac002t98.pdf The bad news is that Toyota thinks you should replace all the o-rings. (In which case, heck, you might as well flush out the oil.) If it makes any difference, my 9308 R12 orings are all reddish-pink. I believe modern R134a compatible orings are green.

I'm in the process of replacing a compressor; let us all know what you decide.

hiluxhack

Update. It had a sticker on the rad header like millball said. R12. Weird thing is the new liquid line had a low side 134 a fitting. Go figure. So I vac and filled with 134 a and changed both fittings to the correct ones respectively. Thanks guys for sharing your knowledge. It cools so well it gives me an icecream headache now.