Hi everyone,

I'm still a fair way off finishing my car but I am always trying to think ahead.

I am trying to decide what to do about the factory aircon fitted to the car.

To get it up and running by law the R-12 refrigerant must be changed to R-134a. This in itself is not a problem as it is the law in this large round green house we all live on.

My main concern is the COST of getting it done, as opposed to how cool (temperature, not me) I want to be while driving.

As the car is only going to be driven during the late spring, summer, early autumn months and a lot of those days are going to be hot days.

How many of you have converted to R-134a and how effective is the conversion?

Or should I just wind the window down and spend the money on something else?

Alan P.

A former nieghbor of mine who is a heating and air conditioning specialist says that there are a couple of alternative replcements for R12 that only require changing installing adapters on the high and low side valves, removal of the R12 and recharging with the new refrigerant. I believe it's called Freeze12. He says it actually runs 3 to 5 degrees cooler than R12 and doesn't require retrofitting of any ac parts other than the above mentioned adapters. Also, since it's compatible with the R12 lubricants, the system won't have to be flushed after the removal of the R12. It costs much less than R12 and is legal in the US. I have no idea if its available in Australia.

Hi Stephen,

I think this is either the same thing or something very similar http://www.hydrocoolonline.com/tech_info.htm but I can't find anywhere in Aus that uses it.

Retrofitting is not as straight forward as I thought it would be.

Alan P.

Try this site as Autofrost is one of the alternatives my friend mentioned. I don't know about its availability in Australia.

http://www.refrigerantsales.com

Wonder what an entire new system would cost...compressor , receiver drier etc...all but the condenser...anyone have an idea...

I definitely need a new compressor...and there is a leak somewhere in the system which is why I now need a compressor..but Im wondering what it would cost to just redo the system minus the condenser ....

77 Z

MSA has a complete conversion lit for like $650. I have a friend that is AC certified and he says that basically you only need to change out the acumulator, seals and adaptors. Don't use the cheap aluminum ones. You need to flush out the old oil first. I was thinking of converting mine, and will document the process and post it as a how-to artical.

Originally posted by Alan Pugh

How many of you have converted to R-134a and how effective is the conversion?

I converted my daily driver 240SX to R134a several years ago and it works as well as or better than the original R12. I keep a thermometer in the vent and on hot days here in Atlanta (90 degrees F or 32 degrees C) it routinely blows air at 42 degress (or 5 degrees C).

I've heard that 134a got a bad reputation in the early days (that it didn't cool as well) because of some improper conversions. As a refrigerant it's just as good as R12 but has some different moisture absorbing properties. You don't hear people complaining about the air conditioning in new cars which are all designed for R134a.

I don't know about converting original 240Z units to R134a; I plan on installing a modern system like what MSA sells as I'd rather have a smaller and more efficient compressor.

Well, it probably won't help those of you on the other side of the planet, but here: http://www.vintageair.com/

If one were building "from scratch", this would be ideal...assuming you don't mind spending $$'s

I am working on this one myself. The '73 I had uses FRIEZE12 in the dealer installed Fridgaking unit and it worked well, I replaced the compressor and dryer, flushed the lines, evacuated, and filled her up three years ago. She blows ice, but does have a strong tendancy to iceup from the 95 plus humidity and not enough airflow through the evaporator.

The '72 has never had AC, I am working on a quieter, more powerful unit, more airflow, variable orface to adapt to varying RPM of city driving, and a better fit under the dash. Any part that can be seen from a comfortable position(to me) must look factory or period and fit properly.

As I sew up the car, I will post the progress-just researching parts now-it will use R134.

Will

It would be nice if we could put together a how-to article with where to get the parts and the step by step instructions on how to inspect and test all of the different components required to bring an old AC system back on-line. I know that MSA sells the entire conversion kit but I sure would hate to spend money to replace something that may be salvagable and functional. If there are any AC gurus out there it's time to share your wealth.

I would just like to know what I might be looking at dollar wise to replace the compressor as well as the receiver dryer and possibly the condenser ...the condenser may be ok..the system had a leak in it when I bought the car and like a dummy I did not have it checked or fixed at that time..we added freon ..well out of nowhere the compressor locked up..so does anyone know if another system will fit in a Z or will only a Z compressor work or whats the story as well as possible financial damage...

Thanks for the imput

77 Z

If you had a piston type of compressor(usually marked British Leyland), replace it with the round Hitachi style, more efficient and usually less expensive ($150-250). The reciever/dryer is usually between $10 and $20, the condensor is about the same as the compressor.

Depending on the year of your engine, a compressor mount from a 280ZX will allow you to use the later style rotary compressor using a factory part, most of the rest of the under hood system will fit with minor mods as well, then you just have to make up some lines for the existing condensor.

You will have to clean and evacuate the system and charge it with A/C oil and freon as well.

An A/C cleaning kit with solvent was about $80 from Napa last year-it requires you have a source of compressed air.

Will