You should do the full conversion. My 95 Miata blows 38F at the vent on R134a.

 

Second on the Freeze-12. It's a blend refrigerant that (while the EPS doesn't want you to mix with R-12.. because then R-12 can't be recovered after that) you can safely mix with the R-12 that's in your system currently and just top up what's missing. It'll probably only cost you $20 or so.

R1's take 12.2 oz, or just a smidge over 1 lb. (tiny *** AC system.) Tourings and base models have a larger capacity. With freeze 12 you get the best performance with a lighter fill (like 90-95% by weight of R12 if I remember correctly) then it's under 1 lb to fill an R1.

 

I've had both the '93 with R12 and now my current '95 with R134a. I can tell you that the 95's A/C does NOT cool as well.

On really hot days (>mid 90's) you need to keep the RPM's up; maybe running one gear lower than you might otherwise. At highway speeds it works reasonably well, though. I've heard estimates that R134a cost about 15% in cooling capacity and I believe it.

I understand that everything in the A/C is the basically same between the years except for the crankshaft pulley. Mazda increased its diameter for '95 in order to help run these accessories at a higher speed.

 

Sorry but thats wrong. I have a 1994 R2 and it takes R12. My buddy has a 1994 touring AT and it has 134A.

I think the difference is the production time, or the manufacturing location rather than the model. In 1994 is when the changed happend but NOT FOR ALL RX7's.

 

??

Where's the difference? I mean, what part of the system is different that allows different capacities?

 

How can you tell which one you have?
I've got a 94 and don't know jack about AC's...

 

If you look at the ports in the AC lines by the turbos, the R12 has smallish ones that look like a schrader valve (like a tire valve stem). The R134a ports are larger and have a quick release set up.

 

lol, or how about you look underneath the hood. Its near all your other specs on the under part of the hood.

 

Sure take the easy way out

 

R1s were shipped from Japan with no AC and had it installed at the port. Condensors and compressors are about the same size but seem to contain less refrigerant..

 

Thanks for the info. I need to hook mine up (from my v mount install) and refill it.

 

My 94 PEP model also has the R12 system...production 08/93.

Question: Why go through the trouble of converting to R-134 system when Freeze-12 cools very well in the R-12 system??

 

Where do I get this freeze 12? I cant buy on my own since i need a license and when I mention it to shops they all say they either dont have it or the only have "a little R12 left". I think they are lying to me to make some $$$. Who can help me out with an honest place in so cal. In torrance preferably.

 

94's are 134a. Here are the differences according to the '94 Electrical Manual:

Compressor Oil: R12 - mineral oil, R134a - polyalkylene glycol oil

O-ring: R12 - NBR or Flourine rubber, R134a - RBR rubber

Joint nuts: R12 - Inches, R134a - Metric

Joint blocks: The manual just says the two systems are incompatible

Charging valve and valve joints: R12 - Screw on (Hi: 3/8-24UNF, Lo: 7/16-20UNF), R134a - Quick-connect (Hi:16mm dia., Lo: 13mm dia.)

Tool Joints: R12 - Inches, R134a - Metric

Manifold Guage: R12 - Hi-pressure-side max. reading 2.9 MPa/430 psi, R134a - 3.43 MPa/500 psi

Leak Tester: R12 - Gas or Electric, R134a Electric only, not compatible with R12 electric tester

 

You don't need a license to buy Freeze-12. It's Not R-12.

How about Freeze12.com

There's other sites that sell it too.

 

You can buy R-12 and R-12 replacements on Ebay for cheap as well

 

sweet thanks for that link.

okay so here is where i need your help. since i am going to buy this stuff.

1. Do i have to convert the ports to put the a/c in?
2. how do i put in the oil needed?
3. can i still use the r12 oil?
4. i noticed that someone already stated that i could "top off" my ac with the freeze 12, but can anyonbe else confirm that that is right? are you sure i dont need to purge the r12?

thanks

Ian

 

Double post

 

That kit comes with the new ports, just like a 134a retro-kit would. I forget where I got my kit from but the port adapter I recieved didn't push down on the R12 valve enough to let refrigerant in. Frustrating. I just used an R-12 hose instead and filled them directly.

If you haven't had any leaks where oil was forced out and you're just topping up a little bit, don't worry about adding oil. You can (on other sites.. look around) buy a 4 oz can of oil to add. You add it the same way as the refrigerant, through the hose.

This is compatible with the R-12 oil.

Here's a page that should answer more questions.. http://autorefrigerants.com/freeze12faq.htm
The only reason to drain & flush your system is if it's been open and collected moisture, or if you wanted to comply with the EPA's mandate. They want you to only have one refrigerant in there so that when you take your car in for service, they can properly recover the R-12, R-134, etc.. and re-use it. I guess I shouldn't advocate ignoring this but oh well. If you don't want to lose sleep, take your car to a service station and they'll suck out your R-12.. if there's any left they shouldn't charge you for it as it's more valuable than the service charge.

 

THX for the info!!!!!

I also looked on ebay as suggested by johnisenglish and it seems like the r12 cans are SUPER cheap!!! Anyone else that needs R12 check it out!

Now I'm torn on what I'm gonna do. Ehh I'll figure it out later.

 

well i just bought a can of r12, gauge, and hose kit (w/tap) off of ebay.

I am wondering if i need to put in oil. NewbernD said " If you haven't had any leaks where oil was forced out and you're just topping up a little bit, don't worry about adding oil", but I'm not sure if I have been leaking any oil. Whn I turn on my a/c now I can hear a gurgling sound coming from the passenger area. Not really sure what that is but it only started after my a/c started blowing warm air. Does this require adding oil? If so how much do i put in? I have an R2 and it can only take 1lbs or 12oz max of r12.

can anyone help me with any suggestions or tips?

 

If it's just low because it's 10 years old then I'd just charge the system again. Don't worry about the oil. With such a small system you deinitely don't want too much in there. That gargling is the expansion valve behind the glovebox. You're hearing it because there's not enough freon in the system.

Because of the gargling I can assume that your compressor comes on. That means you have at least 5 oz of freon in there. Here's the how-to.

You'll be charging through the low pressure side. That's the big tube. The ports are over by the ABS system. Start the car and get it up to temp. You may want to connect the charge hose while it's cool though.

When it's up to temp, turn the AC on, temp to cold, recirculation on and set the fan to high.

If the compressor is running then you'll be charging with the can upright. If the compressor doesn't come on then you'll begin the charge with the can upside down. When the compressor kicks on then turn the can right side up.

You're going to want to watch the surface of the low pressure line. When it begins to show condensation then you're almost there.. Charge it for another minute and no more. Hop in the car.. it should be coming out cold now.

Good luck.

 

That's a good writeup, but doesn't it very heavily depend on the humidity on the day you fill it?

 

I just converted to AUTOCOOL which does not contain any HFC, it is only HC and cools better than R12. You use 1/3 the weight of R12.

The low pressure side for our system will rise to 50PSI, but the high side will drop to less than 150PSI.

So far it is working GREAT!

Go to
http://www.autocool-refrigerants.com/

 

THANKS NewbernD!!!!!

That helps a lot. I thought the low pressure side was the thinner pipe. I'm glad you mentioned that!

As for "If it's just low because it's 10 years old then I'd just charge the system again...", well its been 3 years since the last charge. It's pretty safe to say I have a leak. I just want to charge it up a little so I can get some cool air in the cab until I manage time to go get the leak fixed. I know its bad for the environment but...uhhhh... so is running a midpipe =)

Ill get it fixed soon (i hope). I dont suppose you got a write up on how to find/ fix/ repair leaks in a r12 sys. do you?

now that you know this is a second refill after 3 years do you think i need oil. How do I know for sure that I dont need oil?

Thanks Again

Ian