E9 new AC expansion valve, will it work with either R12 or R134a????

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jjs2800cs

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Restoring 1970 2800CS. All apart and going through all parts.

Going to upgrade AC system with new parallel flow condenser and new real Sanden 508, new hoses, dryer, etc.

But we are pretty much stuck with using the factory evaporator unit. Since we are pretty sure we are switching to R134a, can we still use the factory style expansion valve? In other words are they Freon specific? Are expansion valves in general Freon specific? Still might go with R12, but no around here will charge the system if we stay with R12. We can do our own charging with 134a.

From what we have researched on this forum, it appears that the OEM valves are being used with R134a swaps and no one had reported any issues with doing so that we found.

We have 2 new OEM style URO valves purchased years ago. Any concern using a URO part here as we all know what a pain to replace the valve, them so any comment on that?

We having been watching the thread where one is trying to fit a more modern evaporator core into the stock housing. Would love to go down that path, but waiting of some concrete advantages for all the effort.

Also, even thought we are updating there are still going to be many flare fitting connections. Are the use of the conical washer seals recommended in all those connections? I have read to anneal all the flare copper fittings before using again. We have a supply of new conical copper washers and the old ones which supposedly can reuse after annealing them.


Thanks
jjs2800cs
 
The real issue is r-12 and r-134 use different oils and I believe they must flushed. I am in the same boat with the Chamonix coupe, I have disassembled the evap box before to replace the valve but don’t want to do it again. It is time consuming to remove and disassemble the box but it is a 50/50 gamble on whether the valve is good. I will roll the dice this time and not replace the valve and my a/c guy will use r12 with a new Sanden 508, new vapor barrier hoses but four flare fittings will remain.
 
When you buy your compressor verify that the oil can be used with either R-12 or R-134 and make sure you flush out the evap and lines so old oil is removed.
This ad states that the new PAG oil can be used for either freon.
 
HB Chris said:
The real issue is r-12 and r-134 use different oils and I believe they must flushed. I am in the same boat with the Chamonix coupe, I have disassembled the evap box before to replace the valve but don’t want to do it again. It is time consuming to remove and disassemble the box but it is a 50/50 gamble on whether the valve is good. I will roll the dice this time and not replace the valve and my a/c guy will use r12 with a new Sanden 508, new vapor barrier hoses but four flare fittings will remain.
Click to expand...
Thanks to you and others on your replies. More specific question for you. Will you be using these on the flare fittings. Almost 30 years ago when I installed a complete AC system from a donor CS, when taking apart the system we found the sealing washers on some, but not all the flare connections. We put it back the same way and with R-12 as it was still readily available and cheap then. Just the other day we took apart the expansion valve from the evaporator and there were no copper washers on the fittings, so we must have not used them there.

1654512011257.png

As stated, I would love to stick with R-12 but no one in a reasonable radius as of now wants to deal with the stuff. I do make my own hoses and do all my own work, have vacuum pump, gauges, etc. Just recently put compete systems in VW beetle and a Porsche 914 with no issues, and had them filled of course with R-134a.

So I will install the new system, and at the last minute decide on using R-12 or R-134a. The vendor that I bought the new Sanden 508 says the oil in the new compressor can be used with either. So if I do find a shop that can fill it with R-12 I'll go that way.
 
Flare washers are available at coldhose and other sources.
coldhose.com

Orings and Washers

coldhose.com coldhose.com
There is more info in the DIY section

DIY - Air Conditioning Updating with Sanden Compressor and Parallel Flow Condenser

This DIY is subject to editing. More posts are being reviewed and information will be added. I have tried to credit the people for their original posted information. If there are errors or lacking information in here please let me know. Air Conditioning Compressor and Bracket Selection Posts...
e9coupe.com e9coupe.com
 
jjs2800cs said:
Thanks to you and others on your replies. More specific question for you. Will you be using these on the flare fittings. Almost 30 years ago when I installed a complete AC system from a donor CS, when taking apart the system we found the sealing washers on some, but not all the flare connections. We put it back the same way and with R-12 as it was still readily available and cheap then. Just the other day we took apart the expansion valve from the evaporator and there were no copper washers on the fittings, so we must have not used them there.

View attachment 142325
As stated, I would love to stick with R-12 but no one in a reasonable radius as of now wants to deal with the stuff. I do make my own hoses and do all my own work, have vacuum pump, gauges, etc. Just recently put compete systems in VW beetle and a Porsche 914 with no issues, and had them filled of course with R-134a.

So I will install the new system, and at the last minute decide on using R-12 or R-134a. The vendor that I bought the new Sanden 508 says the oil in the new compressor can be used with either. So if I do find a shop that can fill it with R-12 I'll go that way.
Click to expand...
Mechanics don't want to deal with R12 because of the expense of training and certification. For small independent shops, the costs can't be justified.

That said, many junk yards have access to people with current certifications.
 
jjs2800cs said:
Thanks to you and others on your replies. More specific question for you. Will you be using these on the flare fittings. Almost 30 years ago when I installed a complete AC system from a donor CS, when taking apart the system we found the sealing washers on some, but not all the flare connections. We put it back the same way and with R-12 as it was still readily available and cheap then. Just the other day we took apart the expansion valve from the evaporator and there were no copper washers on the fittings, so we must have not used them there.

View attachment 142325
As stated, I would love to stick with R-12 but no one in a reasonable radius as of now wants to deal with the stuff. I do make my own hoses and do all my own work, have vacuum pump, gauges, etc. Just recently put compete systems in VW beetle and a Porsche 914 with no issues, and had them filled of course with R-134a.

So I will install the new system, and at the last minute decide on using R-12 or R-134a. The vendor that I bought the new Sanden 508 says the oil in the new compressor can be used with either. So if I do find a shop that can fill it with R-12 I'll go that way.
Click to expand...
I don’t recall but I used new hard lines from CoupeKing and put those in myself. I would buy new.
 
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