A/C in 280z

[IdahoKidd]

My 77 280z has a non working a/c. There is a sticker with some details on the hood. Was the a/c installed factory or is it a dealer item? Can it be brought back to life with the new freon replacement or is it just too much to deal with?

Thanks,

Leonard

[Ttiger]

The 280Z had factory air. You can tell by the A/C hose ends with threaded fittings, not hose clamps.

If the compressor is good, I'd replace the drier (about $20 - generic) put a vacuum pump on it (Harbor Frieght has a cheap one that works off an air compressor). Suck it down, checking for leaks and put some R134a with oil in it.

[sblake01]

Actually they used both factory and 'dealer installed' air in the 280Z. Ttiger's description of the hose differences is one way to tell the difference. Also if it has a 4 speed fan, it's factory and if it has a 3 speed fan it's not. I disagree with using R134a in a system designed for R12. I'm a licensed HVAC/MVAC tech. The R134a molecule is much smaller and requires higher pressure to operate efficiently. Both of those factors will untimately cause leaks. The R12 alternative I use is called Freeze12. We've discussed it here a few times. Do a search.

[Jeff G 78]

I know I should search rather than asking, but since we are on the AC topic, how can I tell if the compressor is good? I do not have the AC compressor installed in my Z and really need to get it working. Z cars really suck in the humid late-summer days. Black vinyl and poor air flow don't go well together.

[sblake01]

I cap the hose ports and pull a vacuum through the service ports. Not an infallable test but if it passes that there's a good chance that the compressor will work.

[Jeff G 78]

I cap the hose ports and pull a vacuum through the service ports. Not an infallable test but if it passes that there's a good chance that the compressor will work.

Is that just a static bench test Stephen?

[sblake01]

Yeah, basically. You can also lock up the clutch (a 9v battery will work) and spin it by hand and see if you can hear a 'pulse'. Both of those are what my dear Dad referred to as 'country tests'.

[Ttiger]

A long time Z mechanic friend said he's used R134a in R-12 systems without any problems for years. I have also heard the Freeze 12 is very flammable and most technicians are not using it.

[sblake01]

I'm a licensed HVAC and MVAC tech. Everyone has their prefference, I guess. I've spoken with other techs and the opinion is fairly split. I go based on my own experience for the most part. I don't do much based on things that I've "heard". I've done some testing and plenty of research. But that would be another thread.

Edited June 23, 2009 by sblake01

[richard1]

in my 240z and it is cold and first class. After much research and comments from the experts, i must say that it is the best choice for an original vintage system with typical rubber hoses of the time. 102 F here today and it is very comfortable in the cabin.