This seems to be the mystery of the ages. No one seems to know what this is, the Climate Control Manual in the FSM says nothing about it, and I have no sticker on my car indicating what it should be. Or at least I don't know where such a sticker would be after almost 30 years.

Why would it be too late to go back to R12? Couldn't I flush the system and use R12/mineral oil? Or some other product like Freeze12?

I agree, what is my next course of action? New compressor, flush, recharge with 60% of the R12 charge (whatever that may be)?

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cbjukraine
'84 300D

I have an '82 300D with the original sticker: 2.6 lbs R-12.

That would put you at around 85% of the R-12 charge, which is what some a/c shops use on R-12 to R-134a conversions.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

Thanks tangofox007, where is that sticker located on your '82?

Any reason to thing there would be difference between an '82 and an '84 regarding the R12 charge?

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cbjukraine
'84 300D

Top of the radiator support, passenger side.


No reason that I am aware of.

__________________
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

the sticker on my 82 SD states the 123 is 2.6lbs r12,


the sticker on my 87 124 states both the 123 and the 126 contain 2.9 lbs... odd


I'm pretty sure in 84, the condensers in both the 123 and 124 got smaller tubing and more tubes, this would alter the amount of liquid the system could contain.
odd that it would increase the 123's charge, but lower the 126's...

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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 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

It's in the low 70's and rainy here in Dallas today. Got in the car to take it to an A/C shop to get there opinion...

No noise from the compressor, smooth and quiet as normal.

Does this confirm your suspicions that my system is over-charged? Lower temps mean lower pressures meaning less stress on the compressor? Is my logic correct?

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cbjukraine
'84 300D

Maybe. Flow lower, pressure lower temps lower

__________________
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 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

With it raining and the cool front, the high side pressure would be lower, possibly eliminating the noise.

If you are in Dallas and want to take it to a shop, take it to McCain's. One of the best auto a/c shops anywhere. They are on Floyd Circle near the Floyd Road TI plant. The one at 75 and 635.

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

Annoy a Liberal, Read the Constitution

I've noted that difference before asking the full charge question on here in the past for my old 84 SD. My 84 was 2.9lbs R12, but many other people from other years with 126 SDs showed me a pic of their tag and it was 3.3 lbs. It seems the charge amount did change over the years for the same model.

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2009 ML320 Bluetec
1985 300CD
1981 300TD

Past Mercedes
1979 300TD
1982 300TD
2000 E320 4Matic Wagon
1998 E430
1984 300SD
1980 300SD

Cool, I always wondered about that place if it had a good rep and all. I'll keep this in mind for the future. Thanks for the info Larry.

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Eric in Plano,Tx
85 300D 277K overall miles
65K on WVO (2 tank)
Rebuilt Transmission at 245k miles.

96 CE LT1
94 Nissian Hardbody
96 F250 XLT PowerStroke (also runs on WVO)

I haven't dealt with them in a few years so to make sure they are still a top notch shop, just ask for Mark. He used to be the owner and is VERY helpful and approachable. If he is still involved with the outfit, then you can have all confidence in them. They also sell supplies and parts over their parts counter and Mark will give you any information you ask for with no obligation. He just wants to help people.

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

Annoy a Liberal, Read the Constitution