AC for Datsun 240z

[Dice T]

Hello, I'm brand new to the forum as I just bought a 1973 240z. The car is extremely well kept and runs very strong with everything original and stock. I'll have pictures of it up eventually.

 

However, the car has two problems, one of which I don't know how to solve.

 

The AC doesn't work. The previous owner told me all the parts are there and all it needs a freon recharge. Problem is, I dont know where the valve for the freon recharge is!

 

So to the almight members of the ratsun community, where is the valve for the freon recharge?

 

 

[Dguy210]

Cars never just need a freon recharge.

If it is low on refrigerant that means you have a leak of some type, this needs to be fixed before you refill it. Also, a '73 is most likely R12 (unless converted to R134a, and if done correctly will have stickers saying so). You will also want to fix the leak because R12 is pretty expensive, not counting the whole venting to the atmo thing (other reasons too involving compressor lubrication).

 

You will probably want to take it to an A/C guy who does R12 (different connectors then R134a) and get a diagnostic first. Is it just low on refrigerant, is it completely gone? Does everything else work etc...

 

If you want to tackle this yourself it can be done, just realize once you expose an A/C system to air there are a couple of things that pretty much have to be replaced, and if you want to run R12 you need a certificate (not that hard to get), you will at a minimum want a decent set of gauges. Pumps, and recovery systems can be rented, or borrowed. I would suggest staying away from R134a, it is NOT a direct drop in replacement, you will need major modifications to do it right, and it is not as efficient.

[Dice T]

Thanks for all the great insight. I know a couple of AC repair shops in my area that i'll take my 240 to once I save up money again :D

[Dirk Diggler]

Does it blow at all? I wouldn't take someone's word as the problem

[HRH]

Don't forget, R12 is ghastly expensive. Better make sure the system is worth saving. Me, I'd yank all that shit off and enjoy the weight savings. I see you're in Texas though, that might be hotter than snake balls.

[Dguy210]

Don't forget, R12 is ghastly expensive. Better make sure the system is worth saving. Me, I'd yank all that shit off and enjoy the weight savings. I see you're in Texas though, that might be hotter than snake balls.

 

 

The place to get R12 "cheap" is ebay, you can find it for about $20 a can, which is only about 2-3 times that of R134a. You need the cert for it which is an easy online test and ~$20.

 

 

(For the OP): There are a few hydrocarbon based R12 "drop-in" replacements available (mostly propane blends), that run a bit cheaper, these are not the greatest for other reasons though. Stay away from crap like Freeze 12 or others that say they are a direct replacement. I can go on a tirade about this, but this one is pretty easy to Google.

 

If you want details, I've already gone through all the research to legally rebuild an auto A/C system on an older car (and did so). Not really that hard, just expensive and you need to be kinda meticulous about leaks, cleanliness, and doing things correctly.

 

And yeah, in Texas A/C is almost as important as brakes

[king bee66]

you get used to getting out of your car with a sweaty shirt after awhile and you think nothing of it :hmm: i have an ac set up but im afraid of overheating

[Dice T]

Thanks for all the info guys. I went around and no one in my immediate area will/can do a R12 repair. One shop even said that they haven't done a R12 repairs since the 80s. However, the same shop said they can do the conversion to R134a including the compressor and retro fit + labor for around $660. Does that sound like a good deal to anyone? I really have no idea. I looked into buying the parts myself from zcarparts and it ran for around $1200. A little expensive. Any suggestions?

[Dice T]

I saw that some people put vintage air into their 510s. Anyone try it with their z?

[Dirk Diggler]

So does the blower work and its just warm air, or does it not blow at all?

[Dice T]

It blows, but really warm because of the TX heat.

[MicroMachinery]

My uncle runs a refrigeration business, and uses r414b(aka "Hot Shot") as a direct replacement for r12. He charged my A/C in the 610 and it cooled GREAT.. down to 32F if I remember.. but it leaked out in a couple days :( Still need to find that leak..

 

If everything in your system works, I would stick with r12(or r414b). It's superior in alot of ways, but yes, more expensive. I'm not sure if it's more expensive than a $1200 bill for A/C that doesn't work quite as well, but per can, it costs more. Keep searching. Alot of people say screw retrofitting, because they realize that r12 is the best for optimal A/C.

 

However, if your system needs to be gone through and replaced anyway, just get up to date r134a stuff. Finding parts will be alot less of a headache.

[Dirk Diggler]

A local guy is selling r12 for 35 bucks a can on Craigslist here, says he has many cans. If you're interested, I can probably talk him down and you pay for them and shipping and I will get them to you