DIY: R-12 to R-134a Conversion (How To)

JDMMA70

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tlo86;1871181 said:
for the love of god please try to keep any moisture out of the system ;) it does take time for it to eat away at your system, i have heard 100 stories of 'well i converted it now it doesnt work (year later)' or 'i just replaced the schrader valve'... on and on.. i would have a shop evac the system after the work just in case. why do all of that for nothing :p

if you are getting a new compressor or performing any work you might as well replace the orifice tube/expansion valve and receiver drier... these are cheap parts to replace... about 15$ each. most warranties require the work and at least some proof of a shop performing the work.

Im not sure if you are referring to my DIY but, I did evac the system thats what the vacuum pump is for...and i covered replacing the TXV and Drier, and even the condenser. Why pay a shop when you can do it yourself hence the sticky :)
 

JDMMA70

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My understanding is the stock condenser is a serpentine type. Plus the fin density is greater on the parallel flow unit which should allow for better heat transfer I would think.
 

CyFi6

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Parallel flow condensers are around 25% more efficient at releasing heat than a serpentine condenser of the same size. The ACI PF condenser is very slightly smaller but makes up for it in efficiency. The PF condensers use micro channels which are much smaller than the channels in the serpentine condenser.
 

steven89

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Well! Finally got my car running and to the point where I can drive it around. So heres what I have to say about the conversion, or atleast what all was done to mine which im sure Derek can clarify.

ITS COLD! Like it gets as cold if not colder than my moms Mazda 5! I had it set to 65 until it managed to cool the cabin, then after a while I started freezing it got so cold. I had to put it to 78* just to keep from freezing with it on. I was very surprised at how well it performed! Id highly recommend converting to R-134a if you don't have an already working R-12 system (or no AC at all).

I need to find a thermometer of some kind to find out how cold it actually gets at some point. But for now, Derek (JDMMA70) is awesome!

Thanks!
 

Doat

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Could you just convert the system to R134a then take it somewhere to have it vacuumed and recharged? I plan on doing this conversion then taking it to a friend of mine who runs a shop to have him run a diagnostics on my AC system to see if I have leaks or need to change anything then recharge the system. Also is there an O ring kit that Toyota provides or do you have to get them all separately?
 

JDMMA70

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Doat;1875403 said:
Could you just convert the system to R134a then take it somewhere to have it vacuumed and recharged? I plan on doing this conversion then taking it to a friend of mine who runs a shop to have him run a diagnostics on my AC system to see if I have leaks or need to change anything then recharge the system. Also is there an O ring kit that Toyota provides or do you have to get them all separately?

You can but its not that hard to acquire the tools needed to do the vacuuming and charging process. Vacuuming the system will tell you if you have any major leaks. Minor leaks if there are any after you change all the o-rings wont show themselves until its charged. So really if you do everything correctly you shouldn't have a o-ring leak. The only place i can think of that you'd have a leak is the suction and discharge line coming from the compressor. This is too easy to have to pay someone to do it for you. Toyota doesn't sell an o-ring kit, i just ordered all the sizes i needed. Like i said you can use a green o-ring kit like the one pictured in this thread on page 2.
 

Doat

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JDMMA70;1875437 said:
You can but its not that hard to acquire the tools needed to do the vacuuming and charging process. Vacuuming the system will tell you if you have any major leaks. Minor leaks if there are any after you change all the o-rings wont show themselves until its charged. So really if you do everything correctly you shouldn't have a o-ring leak. The only place i can think of that you'd have a leak is the suction and discharge line coming from the compressor. This is too easy to have to pay someone to do it for you. Toyota doesn't sell an o-ring kit, i just ordered all the sizes i needed. Like i said you can use a green o-ring kit like the one pictured in this thread on page 2.
How does the green kit compare with OEM? Also how difficult is this compared to say changing a head gasket? That is something I did this past summer and this seems pretty easy compared to that lol.
 
May 18, 2007
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JDMMA70;1875320 said:
Its on my guide 1st page

I'm sorry I must be blind then. I can see what you write about old amount + some new oil, but if I don't know the old amount? How much to put in a completely dried out system?

I'm sorry if you wrote it, but I can't find it.
 

JDMMA70

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Doat;1875460 said:
How does the green kit compare with OEM? Also how difficult is this compared to say changing a head gasket? That is something I did this past summer and this seems pretty easy compared to that lol.

Very easy if you follow the guide step by step. Green Kit is very similar to OEM as far as i know, ive used them before never had an issue.

Kristian_Wraae;1875475 said:
I'm sorry I must be blind then. I can see what you write about old amount + some new oil, but if I don't know the old amount? How much to put in a completely dried out system?

I'm sorry if you wrote it, but I can't find it.

No worries. The old amount of oil will come out of your compressor. If its dry and there is no oil in the compressor make 20ml your old amount and go from there.
 

Doat

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Wow it's only 9 bucks, when I get the adapters from NAPA should I also replace the cores or does it come with new ones?
 
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JDMMA70

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Doat;1876253 said:
Wow it's only 9 bucks, when I get the adapters from NAPA should I also replace the cores or does it come with new ones?

Depends what type of adapters they are. However always replace the cores