So I've decided it's high time to get the A/C working in the Mazda. It hasn't worked in years, and I never bothered with it, but these last couple of weeks in SW PA have been pretty bad with temps around 100°F and humidity around 90%. I've searched and have somewhat of a clue but there's still some things I'm not sure of.

Last time I messed with it, I put a new engine in and thus had opened up the A/C system. It's all back together as of now though, but has no refrigerant in the system. Assuming the compressor works, and it did when I forced it to, what needs to be replaced and checked to get the system working again? I know for a fact that the PO had ran r134 in the car but it's been empty for a number of years now. I plan on running freeze12 when all is said and done. So basically what do I need to do from where I am now to a running system.?

 

Well, you need to make sure all the r134a is out first off by vacuuming out the system which will also help tell you if you have a leak. Then, assuming no leaks, I'd replace the receiver dryer/accumulator, don't know what the 7 has. Then, vacuum again to remove what little moisture probably entered from doing that and then charge it up.

 

Simple enough. One more thing. I recall that there was a special o ring where the lines come into the top of the compressor, and that the green o rings they sell would not seal it. Anyone got a source on it?

 

Hopefully somebody else will chime in on that. I'm still running with an empty A/C system, though these 100*+ days with 110*+ index in IA are killer, so I'm thinking about working on it here soon.

 

I don't think it's a special o-ring. The large kit from Autozone (not the small one) has pretty much every o ring you will need. Worked fine in my car.

Check this thread out - it's going to save you money.

https://www.rx7club.com/2nd-generati...ht=REFRIGERANT

 

You might check this out, but I can't guarantee it'll have it in there. I can't find it on Mazdatrix though.

http://www.oreillyauto.com/site/c/de...6500&ppt=C0328

For legal purposes, you need to have the system recovered if there is R134a in it. That means you have to take it to a shop, where they'll charge you to take the R134a, store it in a container, and re-use it where they'll charge someone else for it. That's the uh... right answer. :/

Then you can vacuum it, check for leaks, charge it with whatever refrigerant you want. I used Jackhild59's writeup for converting to R152a with great success, but you can use Freeze12 if you feel like dumping 5x the money for refrigerant. If you have an air compressor, get the $15 vacuum pump from harbor freight. I used it with great success, and it drew and held a 25"Hg vacuum on my system. You just have to let the compressor build up pressure, vacuum it down, shut the valves, repeat. Oh yeah, you also need a manifold gauge set to use the vacuum. If you don't vacuum it, the AC will not work like it should.

 

Found that writeup a few minutes ago. Answered all my questions. I remember getting that o ring set from auto zone and trying to replace the one ring, but it leaked from there. The original one is a double o ring and I think the bolt goes down through the middle.