First I have read just about every thread on this subject, so I know there are folks out there who would never do this. This has been a BRUTAL summer in South Texas and lots of other locales. In 2004, I had my 1985 300SD converted to R134a at my favorite indy shop at that time due to a leak repair and the high price of R12. Well, it never was great at cooling after that, but adequate. This summer, I just could not deal with temps in the car. I was getting at best 55 to 65 degrees at the vent at 100º plus temps. I had started driving my V8 w208 which has very cold air as a daily driver. But I missed my SD. So...about a month ago, after doing tons of reading on the subject, I ordered two cans of "Enviro-Safe R134a Replacement Refrigerant with Dye" after being strongly discouraged by my present indy. He agreed to evacuate the R134 from my system, but told me he wouldn't work on my a/c again due to contamination. So I put the two small cans, 5 or 6 oz, in myself. I got a low pressure reading of about 30 from those two cans. On the way home, I was BLOWN AWAY. Vent temps began plummeting...(at about 95º outside) they fell to 45º on Auto fan speed after about a mile of driving. WOW! It got down to about 40º by the time I was home. Today, at around 11:30 with outside temp around 91º, I had a vent temp of about 35 DEGREES on low fan!!!! I wasn't running around with a vent thermometer when I had R12, but I don't ever remember it EVER being this cold. Maybe I made a mistake doing this, but it's an old car and it will die with me...not sure who'll go first. ONE OTHER THING...I can BARELY tell when the compressor comes on. I mean I push the a/c button and the idle speed barely changes. With R134, I could feel the hit of the compressor coming on. Just wanted to share my experience. Didn't think my old SD could ever have air this cold.

I'll stick with LP gas. Just have to fix my leak though!

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1991 560 SEL / 185k miles
1992 750il / 17k miles - project car

How did you decide how much to use?

12 oz is 1/4 the R-12 capacity!

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Current Mercedes
1979 maple yellow 240D 4-speed

Gone and fondly remembered:
1980 orient red 240D 4-speed

Gone and NOT fondly remembered:
1982 Chna Blue 300TD

Other car in the stable:
2013 VW Jetta Sportwagen TDI / 6-speed MT

But I don't know the answer. I know little about a/c systems. I remember reading that each can equaled about a pound of R134a, even though the can was only 5 or 6 oz. It took the full amount of both cans and was still near the bottom of the blue zone of a cheap hose gauge. So I may be undercharged. I do plan to get another couple of cans, in case it gets banned.

That's interesting....I'm tempted to use the stop-leak version of this stuff.

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 159k miles
06 E320 CDI "Rutherford", Black on Tan, 179k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 145k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 77k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife

It's just propane.

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Allen Kroliczek
Oak Grove Autosport | Oak Grove Autosport
01 G500, 82 300TD, quite a few more.....

And if you're amazed: http://www.overclockers.com/forums/showthread.php?t=468525

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Allen Kroliczek
Oak Grove Autosport | Oak Grove Autosport
01 G500, 82 300TD, quite a few more.....

it's NOT just propane...
it's propane/butane blend.

I'd not use the stop leak in any refrigeration system...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Dunno VStech, the MSDS for propane and Envir22a and propane are almost identical - down to 1/100 (0.01) for bp and specific gravity.

butane has a lower limit of flammability, higher specific gravity, and a much higher boiling point.

If there is any butane in there it is not enough to have an effect on the mixture than can be accurately measured. Those differences are just as likely to come from the pine scent they add.


EDIT: Just looked at the Duracool MSDS - I think THAT is likely to be a blend of propane and isobutane, based on the parameters listed above - each is intermediate between the MSDS specs for propane and butane.

It's funny though - the blend doesn't really alter the autoignition point (raises it from 873* to 891*) = which seems like the critical number!

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Current Mercedes
1979 maple yellow 240D 4-speed

Gone and fondly remembered:
1980 orient red 240D 4-speed

Gone and NOT fondly remembered:
1982 Chna Blue 300TD

Other car in the stable:
2013 VW Jetta Sportwagen TDI / 6-speed MT

I don't see the MSDS.

I saw some guy write down three parameters and a set of values.

If there's a link to the MSDS I'd like to see it.

From my investigations I believe it is a HC blend of propane-butane & some other component. Originally it was a pro/but blend but supposedly the DOT would not approve their 6 oz cans for shipping.

So the reformulated to a less efficient but acceptable to DOT. That's one of the reasons the refrigerant has such unusual and stringent installation procedures.

Cool! Literally. I'd like to know the high side pressures.

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My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

High cost of R12?????????????? You mean the $15 a can for R12 as opposed to the almost $10 for R134a???????????

Unbelievable!

Welcome back mate.

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With best regards

Al

you can't get r12 everywhere, and where you can, sometimes there's a premium to be paid

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Not really. R12 is bought all the time for about $15 a pound. Not much more than 134. There are unfortunately some unscrupulous shops that will tell you it is still expen$ive, but those days are gone due to the cars requiring it hitting the salvage yards in record numbers.

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2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

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