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1984 300 Sd
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41 Posts
Discussion Starter #1
Has anyone used the R209 refrigerant (in guess its a propane product) in the 81-85 SD. Did it work for you and how did you do it.? My R-134 conversion does not seem cold enough.
 

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1981 300 SD, 1991 Geo Metro 4-door Automatic
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487 Posts
How cold is your R-134 conversion? With a thermometer stuck in a vent, I get about 40° when on the freeway, and the car feels about cold enough to hang meat. Around town, the temperature goes up a bit, but not bad.

If yours is running warmer, you might want to find out why and fix it first.

Some people on here swear that propane-based refrigerants are perfectly safe, and they may well be, but I'm not yet sold.
 

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1984 300 Sd
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41 Posts
Discussion Starter #3
300SD AC

I dont have a thermometer but it definately is not "meat hanging" cold. Temp here is 90+ now and it is barely tolerable. Have a GMn car that blows way cold and had a 300SD 25 years ago that was great cold even in Las Vegas summer. So, I know it should be colder but how to find the problem?
 

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126: 1981 300SD, 1987 300SDL
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119 Posts
I had an r134a conversion that barely worked at idle and was okayish when driving. It only lasted a year before the AC compressor died with a grinding noise. The car wasn't a daily driver, but still shouldn't have died. Anyway, I'm still working on my system using es-refrigerants.com advanced/industrial refrigerant. I decided to go this route because:

propane is used in AC in other continents and RVs(for everything).
lower pressures than r12 as opposed to r134a which is higher than r12.
I can fix/r&r, fill and recharge the AC system myself without certification (paid shop for evacuation).
Supposedly propane cools better, but I've read that it's hit or miss.

I suppose this isn't much help considering I'm still working on getting my system to actually work (I have another thread on this), but at least I can say that after a lot of web searching, I found a lot of good reasons to go with propane, not to mention you can see charts showing it has relatively no environmental consequence in comparison to r12 and even r134a which I believe is also going to be phased out anyway for some other profit-making chemical industry fashion-of-the-year formula. Besides, I don't know anything about the newest German formula/system which is CO2.

I've heard of people using hardware store propane, but according to refrigerant-grade providers, the odorant, mercaptan becomes a corrosive with moisture and since BBQ propane isn't intended for refrigeration, I decided to go with one that is. Most of these propane providers say their refrigerant is proprietary, but basically it is propane, but refrigerant grade. Being curious, I'm wondering, where and how would you get "R209" (I'm assuming you mean R-290)?
 

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Registered
1984 300 Sd
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41 Posts
Discussion Starter #5
Yes I thought itr was 290 but I saw on a refrigerant suplpier site the reference to R209 with a name of propane. Confuded me and thought maybe I just transposed letters. Still not sure what they were refering to. Thanks for correcting.
 
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