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Discussion Starter #1
Hi!

My new air-conditioning compressor, dryer and expansion valve have arrived!

I've searched for filling quantities, but haven't found anything really definite - I've read 750g for R12 and 950g for R134a.... What's the correct weight?

We'll be filling in 134a btw!

Also, the oil will be changed from PAG to PAO - what is the correct quantity?

The car is a 34000-Series SWB Turbo, so technically a 1991 model!

Cheers

Es
 

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If filling with R134a and the original was R12, you want 80% since R134a expands more.
You must flush the condenser with A/C solvent to clean the junk out of the lines.
DO NOT unseal the drier until use.
You must vac and hold for at least 30 min to check for leaks.
The ORIGINAL qty of R12 is usually printed on the compressor label
Search your compressor online for oil. You put the oil in manually at the compressor. Make sure you rotate the compressor pully to remove all of it.
Double check the type of oil...I use PAG 150 when changeover.

Do you have a manifold gauge set and know how to use it?
NOTE: Your expansion valve has to be calibrated (less) for R134a.
 

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Basically what Wraithman said. You can either charge by 80% of the weight of R12 or go by pressures. There should be a sticker under the hood with the weight. Don't over charge, R134a is less forgiving than R12 and besides, you're in Germany. The A/C does not have to work that hard.
 

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Discussion Starter #5
Hi!
I've got a new compressor, dryer and expansion valve.
A colleague of mine has the apparatus and conversion tables to do the work, but needs the R12 and oil quantity - that I haven't been able to find anywhere!

Cheers

Es
 

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Discussion Starter #8
Thanks guys!

It's all very confusing...
This morning I was pretty sure the correct quantities were 1,1kg R12 and 135cc oil, based on a bit of the TSD 6000 manual for car from chassis 35965....
However, Mike's table suggests 1,93kg R12 and 135ml oil. My old compressor says 1,93 on it, so that speaks for this being right!
I also rang up Flying Spares, where I bought the parts from, and they told me that their technician puts in 1kg of R134a! However, 80% of 1,93kg is 1,54kg...

My colleague with the AC equipment will have a look at it on wednesday (flush it and check for leaks), and then we'll see if we can swap out the parts at the same time!

Couple more questions if I may:

Where exactly is the expansion valve located, and is it reasonably easy to replace?

Does anyone have the part number for the air pump? The one belt-driven off the AC compressor that is! I can't find it in the Flying Spares catalogue!

Thanks again guys!

Es
 

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Hi mate I'm sure when I put r134a in I used 1.15kgs ,but that was years ago and I'm old lol
The valve (if same as mine) is under the scuttle, pig to get at! But there is a tiny filter in it that really needs cleaning ok
Mike
 

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Discussion Starter #10
Thanks Mike!
Don't worry about being old - I'm 43 and can't remember what I had for lunch yesterday 😂.
Do you get at the valve from the engine compartment or from inside the car? I fear that many things are a pig to get at with these cars, but they are lovely cars!
 

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You need to plug in the engine bay, definitely

Read each message of this topic carrefully, you may have a Sanden compressor too
In your owner book you will find filling quantities

See pictures on message 9, you see the H refill plug.....
Read untill the end

 

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Discussion Starter #14
We got the airco running!
Changed the compressor, dryer etc., replaced various o-rings and belts, and flushed the system.
With a refill of 1150g R134a and 135ml PAO oil it now runs perfectly!

Cheers

Es
 

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Discussion Starter #17
We had 6-7°C coming out of the vents, so I'm very happy with the result!

Thanks for the help guys!

Es
 

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Discussion Starter #20
Hi!
That was Mike's suggestion!
The internet has 1000s of opinions, but my airco guy thought 1150g sounded reasonable!

Cheers

Es
 
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