A/C refresh. A few questions...

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Jesper

Jesper

10 Year
Joined
Jul 26, 2015
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Location
Montana
I've searched threads on topic, and think I have the basics but with the costs involved I want to ensure I'm doing it right.

Basically my a/c has never worked since I've owned my 60. Living in MT, it's never been an issue. Now that I'm temporarily relocated to TX/NM/FL thru the rest of the year, it's an issue.

I pulled my condenser and had it pressure tested - good.
Reassembled condenser and all lines with new green o-rings. Installed R134 conversion fittings onto compressor. Charged the system and got nice cold air and was very happy - until I noticed a stream of liquid blowing from the front of my a/c compressor.

I ordered the reman Denso compressor #4710204 from RockAuto.
Also ordered a new dryer/accumulator AC Delco #151975.

I realize the compressor will come filled with oil compatible with R12 and will need to be emptied and filled with oil for the R134. I'm wondering about the dryer...is compatibility an issue, and if so any idea whether the AC Delco model is or can be made compatible?

All other suggestions and advice appreciated.

Thanks.
 
I think u can order r12 still on the internets. I recently did so for my mini truck. It works great. I think that it was an r12 equivalent, not bad for the environment. Worth giving Google a nudge to see what you find.
 
what is the correct Denso part number for R134a drier? I read that the 4780101 is maybe not compatible with R134a but there is a Denso one available that is.
 
Any particular reason you want to go 134?

R12 is still available. yes it costs a bit more...
 
red66toy said:
what is the correct Denso part number for R134a drier? I read that the 4780101 is maybe not compatible with R134a but there is a Denso one available that is.
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Denso makes a R134a compatible drier, but it's only available through Toyota dealers at some highly exorbitant price. If you want to switch to R134a I'd recommend an aftermarket drier.
 
Cool stream will send you the compressor with your choice PAG for 134 or mineral oil for 12. Return rock auto and order from them with PAG
 
1972FJ55 said:
Denso makes a R134a compatible drier, but it's only available through Toyota dealers at some highly exorbitant price. If you want to switch to R134a I'd recommend an aftermarket drier.
Click to expand...

What is the compatibility issue with the drier? I've used new (I'm assuming they are R-12) Denso R-12 driers twice now in R134a conversions, not knowing they were refrigerant specific. Should I expect problems down the road?
 
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Most, if not all, aftermarket driers use a desiccant that is compatible with both refrigerants. For whatever reason, Denso has elected to use a desiccant (XH5) that is only R12 compatible in their over the counter drier. I have asked them on multiple occasions to add the R134a drier (with XH7/9 desiccant) to their aftermarket offerings, but have had zero success.

Cut and paste from Auto A/C Information forum:

We had some studies by SAE Retrofit Committee to show success with used XH5 molecular sieve desiccant that was preconditioned by several years usage with R-12 and mineral oil and did not decompose when used with R-134a. Who knows how much reconditioning is required and how close to saturation the old XH5 is?
desiccant beads are made from activated hydrous alumina (a synthetic form of Zeolite) called molecular sieve. Molecular seize attracts H20 molecules due to positively charged cations that grab and hold the H20) molecules inside the pours. Basically the tinny pours in the desiccant should not be able to absorb the refrigerant molecule.
Moisture has a molecular diameter of 0.28 nanometers (one nanometer = one billionth of a meter). R-12 = 0.044 nm)
XH7 with a pore size of 0.3 nm will allow entry of H20 with it's smaller molecular diameter) w/o allowing the R-134a molecule (o 0.042 nm). Refrigerant molecules are oblong and not round. New dry XH5 with a larger pore size allows entry of R-134a.
Some cheap China R/D use XH9 which is basically for R-22 but will work somewhat with R-134a. The best automotive suppliers use XH7.
desiccant also absorbs acid up to approx 10% of it's weight.
All rubber hoses allow the ingression of moisture and nylon lined barrier hoses are no exception. Actually the nylon liner is a moisture absorber/attractant. It is the outer cover which impedes the moisture entry.
 
Very much appreciate the input. I did check Coolstream out Lopott, but as 1972FJ55 pointed out, the price difference just doesn't make sense for me. Shouldn't be too hard to drain the old and replace with $6 worth of PAG. Hope to have this stuff delivered and reassembled within the next week. This MT boy ain't used to southern NM summers...I'm driving around sweating like Hillary on a polygraph.
 
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