Over filling either one is BAD...
The reason you experience it at ' skin level' with the R134a is that it is less efficient ( given the same system) anyway... so if you compound that by overfilling you REALLY NOTICE it quickly..
Neither should be over filled...
In fact, when I can find and take a picture of it... one of my manuals tells how much below ' recommended fill ' level that the MB system will work ' just fine' at.... as compared to ANY overfilling...
So there really is no reason to ever overfill either type refrigerant....

Yeah, I probablly should not have said anything....I was just happy cause momma's happy...It was on the advice of a Good mechanic and A/C tech that I did that...He's going to put the gauges on it and my MB later in the week just to make sure everything is all right.

And leathermang is right...I have a long history of getting away with things that others do not seem to be able to...I don't know how many times I've had mechanics tell me "I don't know how you got it here"..."That should not even run like that", etc...

"Most days I'd rather be lucky than good...and most days I am"

A little off topic here, but my SDL uses R-12 and is MUCH colder than my 300SD that got converted to R134. I bring this up becasue my friends were commenting how great my ac is.

It's 90plus degrees here and I have to lower the temp inside or I will freeze.

To reiterate Larry's comments from other threads, these cars were designed for R-12, don't convert to 134 ever, if you want your big ass mercedes to be cold.

The cost of the R-12 is so insignificant, relative to the component costs that it makes no sense at all. Do it right.

Thanks

__________________
Enough about me, how are you doing?

May help to read the definition of an Ideal Gas to draw a line and put it in perspective. If you understand what a refrigerant isn't, it may help understand what it is.

When it works it is not difficult at all. When it doesn't work and you are trying to find out why it doesn't work then it may be a challenge.

Anecedotal information does confuse facts.

What I posted above is not complicated, a short bit of reading will make it simple. This is a far cry from rocket science, but there is science involved.

Where is the refrigerant and what is it doing? That is the question.

......

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Therefore MUCH better to underfill R12 than take chance on ANY overfill....

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MB recharging equipment

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MB flushing station..

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More than 2 years ago, I converted my A/C from R12 to R134a with a retrofit kit. I did not do the evacuation, flushing the compressor, changing dryer/receiver. Amazingly after 2 years, the A/C system is still working very well.

Guess I am also very lucky.



David
________________
1985 300D Turbo

"Anecedotal information does confuse facts."
So true.... too many times...
That is why I try not to say anything on AC which I can't photo from a manual and post if challenged.... LOL

Hello All,

I am new to the forum since I found this on a search for A/C repairs on my 87 300D Euro model 135K miles.

A/C has never been a problem for 10 years until this year, when the A/C clutch would not engage, hoping it was not the clutch or compressor but thanks the this forum I was able to engage the clutch by jumping out the hi/low switch then determined via sight glass alas no refrigerant.

Then after reading this thread learned system needs low pressure for switch to activate - Thanks for that. Now to recharge..

I have 10-12 oz cans of R12 so supply is not an issue, and know A/C systems (have worked on commercial systems) and proper methodolgy is to vacuum, leak test then recharge. However I don't have this equipment and want to load one 12 oz can and check results (system holds 2.2 lbs)

Any problems with this approach? Also where can one find the clip on attachment for the small cans - as I had one years ago and can't seem to locate these in auto parts stores.

Thanks

Carl

What is the current situation with regards to your AC ?
You are wanting to charge the system without vacuuming it ?
You are wanting to charge it without using gauges ?
You are wanting to charge it without putting a new Reciever/dryer on it ?
You are wanting to charge it without flushing it ?
You are wanting to charge it without putting new moisture free oil into the system ?

Have you checked to see how much it will cost to fix it if you mess it up by not following the rules ?

On aircondition.com I read that the side puncture taps were nice... and I found mine at my local John Deere tractor place...about 10 each ( one for 12, one for 134)

So Greg. Does this mean any time the system is slightly low, the system should be emptied, evacuated and charged by volume?

Have a great day,

No, on the contrary, it shows that it can be pretty low and still function...

But if you did take it all out... you should charge by WEIGHT.....

Yes,

That was my intent to charge with one can and test for leaks and then take the necessary actions at that time.

I have not looked into the cost of a local A/C vac, leak test and recharge however I estimate it would be $150+ range. I suppose that is cheap versus a new compressor.

Also, I was under the impression that the R12 contained lubricant?

Thanks and I will look into the JD dealer for the connectors. B ut also chek locally on the proper methods..