Replacing A/C in '82 Mustang, converting to R134a

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WylieCoyote

WylieCoyote

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Hi all, I decided rather than fight the R12 ban situation, (my a/c needs to be charged) I'm going to just convert to R134a. Since the car is so old, and all the A/C parts are original to it (it cycles, but doesn't cool very well) I've ordered an OEM-style replacement compressor, condenser, hoses, orifice tube, core & cap kit, seal & gasket kit, and a drier. Since all these components only totaled $312, I felt like it was worth it rather than attempting to flush the old refrigerant oil out of everything and still have a clog.

This lead me to ask the question of whether or not the drier RockAuto offers for an '82 Mustang is compatible with R134a.

It's a Global Parts Distributors (GPD)1411345. I've searched until my fingers bled for any indication of what it's compatible with.

Should I be safe & source a drier that states 134a, or is it safe to assume that anything they're selling in 2018 is R134a compatible?


Picked her up from the original owner last weekend. 64,000 original miles.

 
Just use "winter mix" propane.
thumbsup2.gif
 
The desiccant bag in the receiver dryer doesn't care if its R12 or R134 otherwise its just an empty storage can. Using one that has had oil for a R12 system could be an issue as it would have some oil residue in it.
 
Have not worked on a Ford ( or Mercury / Lincoln ) A/C in ages .

If I had to bet , I would say it will be OK .

Does it have a low pressure switch on the dryer ? If so , you may wish to get one set for R-134A . The pressures are somewhat different .

I used Nylog Blue ( slime ) on all the mechanical connections & O-Rings . For R-134A and R-410a .

https://www.amazon.com/Refrigeration-Tec...ords=blue+nylog

Did you buy the evaporator ? They are often a big chore to swap out .

How about a high pressure switch .
 
Originally Posted By: Trav
The desiccant bag in the receiver dryer doesn't care if its R12 or R134 otherwise its just an empty storage can. Using one that has had oil for a R12 system could be an issue as it would have some oil residue in it.
r12 and r134 use a different dessicant. Back to the original question. As long as the dryer was made after 1994 it will be compatible with r134a. The brand the o.p. is looking at was not even around in 1994. So yes its comparable wit r134a. We still sell r12 where I work. Its not banned. Just no longer made(legally).
 
Any newly manufactured drier will be 134a compatible. Very old ones made in 1970s or before had plastic parts inside made of a type of plastic that would dissolve in R-134a.
 
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Originally Posted By: mk378
Any newly manufactured drier will be 134a compatible. Very old ones made in 1970s or before had plastic parts inside made of a type of plastic that would dissolve in R-134a.
the dessicant and bag are different.r134a eats the bag which drops the dessicant, then it gets pumped around the entire system and plugging everything.
 
Back in the 80s I changed two Fords over to 134. I bought the kit at WM, exchanged some oil for the ester oil the kit had, and charged the system. No parts were replaced in the system. It cooled, but not as effective as R 12, but much better than nothing. I drove the vehicles for several years after that with no issues.
 
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Looks great and reminds me of the 79 notchback we had when I was growing up. Had the 2.8 V6 and auto and started my "hobby" with foxbody Stangs.
Sorry to be off topic but what are your plans? What engine is in there?
 
Originally Posted By: WyrTwister
Does it have a low pressure switch on the dryer ? If so , you may wish to get one set for R-134A . The pressures are somewhat different .

Did you buy the evaporator ? They are often a big chore to swap out .

How about a high pressure switch .


Now that you mention it, there is a switch on the current dryer.

Didn't get an evaporator. Was hoping since that's the only component that will need flushed, it can just stay where it is.

Not even sure about a high pressure switch. Suggestions for the switches?
 
There may not be a high pressure switch. If there is one it is likely in the back end of the compressor. A high pressure switch is nice so the hoses don't blow if something goes wrong, which is more likely to happen with 134a since it condenses at higher pressures than R-12.

A bare minimum conversion would be to remove the compressor from the car to change the oil in it, and replace the drier. Do not use the aluminum port conversion fittings found at most parts stores, they will leak. There are gold-colored steel conversion fittings that work much better.
 
Just so you don't think I'm taking this on myself, I've actually found an A/C shop to install this stuff & charge it up. There's a lot of things I can take on myself, but this isn't one of them. :)

I ordered these steel conversion fittings:

I'll have to ask them what they'd like to do about the switch on the current drier. I guess it's going to be a matter of finding a drier that can accommodate the switch. The one I ordered can't.

 
If it cycles, there is R12 in there. Therefore, regardless of your concerns about a "ban", it is your duty to get it properly evacuated and recovered.

With a simple EPA license, one can acquire R12. There is lots around, to the point that the prices are lower now than they were in the past. There is a challenge finding shops willing to work with it in some places, but again, the legal requirement on you, regardless of EPA license or not, is to find one to have your system recovered (since you say that it does work and cycle, it means there is R12 in there).

Id advise to consider staying with R12. While replacing the condenser is a major step in assuring reasonable performance with R134a, and youre doing everything right, Id hate for you to be disappointed in the conversion not cooling well enough in TX heat. If your replacement condenser is the OE R12 style, it wont work that well for R134a.

I did run a successful 134a retrofit (kept OE evap and condenser, but replaced other parts, fully flushed, etc.) and it worked well enough for a decade of mid-atlantic use. But depending upon where you are in TX, higher heat AND humidity may cause you to not be as happy with the performance. In mine, it was "good enough" until it was >100F.

I keep R12 in both of my early-80s Mercedes cars, and they run beautifully.
 
Originally Posted By: WylieCoyote
Originally Posted By: WyrTwister
Does it have a low pressure switch on the dryer ? If so , you may wish to get one set for R-134A . The pressures are somewhat different .

Did you buy the evaporator ? They are often a big chore to swap out .

How about a high pressure switch .


Now that you mention it, there is a switch on the current dryer.

Didn't get an evaporator. Was hoping since that's the only component that will need flushed, it can just stay where it is.

Not even sure about a high pressure switch. Suggestions for the switches?


May be wrong , but best I remember , the EPA mandates a high pressure switch . Rated at something like 400 psi ?

Look online ( Google search ) or you might check

https://www.oreillyauto.com/detail/murra...evrolet/caprice

I can not tell you where , in the high side , to install it . Maybe ask the people you are purchasing the compressor from ?
 
I was going to convert my 240sx to R134a but when I went shopping for parts to do it, seeing how easy and relatively cheap R12 is all over eBay I talked myself out of it.
 
Originally Posted By: Chris142
Originally Posted By: mk378
Any newly manufactured drier will be 134a compatible. Very old ones made in 1970s or before had plastic parts inside made of a type of plastic that would dissolve in R-134a.
the dessicant and bag are different.r134a eats the bag which drops the dessicant, then it gets pumped around the entire system and plugging everything.


The last one I got has R12 R134 on it. I don't know, but if it was made after 94 its going to be compatible.
 
So the switch on the drier would be low, and if there's a switch on the compressor, it would be high?

Can't even see where electrical plugs into the compressor. Must be on the bottom.

I guess I'll start my hunt for a drier with a switch.


 
Originally Posted By: 555
Looks great and reminds me of the 79 notchback we had when I was growing up. Had the 2.8 V6 and auto and started my "hobby" with foxbody Stangs.
Sorry to be off topic but what are your plans? What engine is in there?


My sister had a '79 notch, which began my love for these cars. This one ('82) has the 3.3 I6, which NOBODY makes a retrofit kit for. No plans beyond keeping it stock & fixing all the little things. I will say that if the A/C doesn't get resolved, it's for sale. Texas is too hot for 2-40 A/C. :)
 
Just to confirm, the port on top of this drier isn't for a switch, correct?

Thanks for your help. Amazing the things I've overlooked.

 
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