Hi All,
Pardon my ignorance here, but which is the low side port on the big V2 compressor (the two cylinder one used on older Chrysler products). I'm thinking of converting mine but after looking at it I'm not sure which is the low side port-Is it the one on top of one of the cylinder head portion of the compressor or the port in the middle top portion of the compressor.
Any suggestions or experience here greatly appreciated!
Thanks
Todd

The suction port is the one on the cylinder head. Do not proceed with an R134a retrofit until you do a lot of research. Just dumping in one of those "retrofit kits" from the parts store will result in poor system performance and early/expensive system damage. The topic has been discussed at great length on this site, see Here, Here, Here, Here, and Here.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Dan is correct. In general the easy way to identify which fitting is which is to l look at the lines. The suction or "low" side will be a larger tube, on the order of 2 or 3 time the diameter of the "high" side. Usually the suction side will be foam insulated while the high pressure side is not.

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

Yep, low side is larger, but no foam insulation on it in the Chrysler applications (except on certain models where bands of foam were used for abrasion protection where the line passes close to other components).

The low line connects to the rear of the V2 / RV2 compressor. The high line connects to the front.

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Too many people who were born on third base actually believe they've hit a triple.

Why not use R12? The system was originally designed for it, no retro fit problems, and although can be somewhat pricey now, is still available from most AC-type shops. I checked at all 3 local Chrysler dealers and all 3 have it in bulk containers.

Yep, all of those are very good points, and are discussed in detail in the linked threads. R12 systems work best with R12.

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Too many people who were born on third base actually believe they've hit a triple.

Unless the law has been changed, it is illegal to sell R-12 to an unlicensed person. I still have some in a bulk tank from the days when it was readily available. I suppose I should take it somewhere at see if I can legally dispose of it. I don't know if it goes bad but I expect I've had it at least 10 years.

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

You are correct, it has been illegal for many years now for unlicensed persons to purchase R12.

R12's shelf life is infinite, it does not go bad.

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Too many people who were born on third base actually believe they've hit a triple.

Thanks for all of the excellent info folks. I'll have to get the condensor, replace my shaft seal and drier (for starters) and work from there. I'm pulling the radiator and figured I might as well fix the A/C system while I'm in there. The subject vehicle is my 66 Dart with factory A/C-sooooo.. I'm assuming that it already has the compressor cycle switch...hopefully. I'll look later today to verify.
Thanks again!
Todd

Yep, the '66 Dart factory A/C system does have the clutch cycling switch system, so you're all set there. That system is undersized for the job it's asked to do, even with R12. You will definitely want to do everything you can to maximise system efficiency before changing to 134a, or you're gonna sweat. Put in the biggest parallel-flow condenser you can find, and make sure you've got a fan shroud and a heavy-duty fan. You'll need to replace all the system O-rings. You won't find the original horizontal-style filter-dryer, so you'll need to go to an alternate setup. There are some horizontal-type units that can be adapted in, or you can just go to the more common vertical style mounted either on the front face of the radiator support panel (next to the condenser) or on the inner fenderwell. Look into having your windows tinted with a quality film (e.g. Llumar); that will seriously reduce the heat load inside the car and make the A/C more able to cope.

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Too many people who were born on third base actually believe they've hit a triple.

The guy I bought Kermit from some years ago had just shot a bunch of 134 that he got from wal-mart with a charge hose into the A/C system. It actually got cold until it all leaked out of the crack in the condenser. I put a good junk condenser in, installed 134 compatible oil, evacuated the system and shot in 134 and hoped for the best. It still cools great almost six years later, and it gets USED here in central GA. No new O-rings, no new nuthin. I ordered a new dryer, but it took too long to get here so it's still got the old dryer, too! I put in one can of 134 every couple years. I have a huge stash of 12, but I figger why waste it? I put the 12 in the ones that I DO fix right. Of course, as mentioned by many, the 134 shot straight into a system designed for 12 is marginal cooling @ idle. The three row radiator I installed has helped this, as has the throttle kick I put on the ole 1920 holley that bumps up the idle speed a bit when the compressor is engaged. The real fix, as mentioned, is additional condenser capacity. One question: How should I plumb this additional capacity? I'm thinking of adding another smaller condenser in line with the main one with its own electric cooling fan (perhaps in the hood with it's own scoop! ) ...should this come before or after the main condenser? Opinions?

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If it ain't broke, fix it!

My opinion: Quit futzin' around and do it right, with a single large-as-possible parallel-flow condenser.

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Too many people who were born on third base actually believe they've hit a triple.

I don't have one of those layin' around... You keep citing this "single large-as-possible parallel-flow condenser" thing - any suggestion as to where to look for one? My other issue is, the 134 transfers a LOT of heat to the engine cooling system during the mega-humid endless summer we have here. I think I want to pre-cool things a bit before it gets to the stock condenser.

D/W

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If it ain't broke, fix it!

Here or Here or Here.
The R134a doesn't transfer more heat than R12 would.
Naw, you don't. The only way to do so would be to place your aux condenser under the car with its own fan. That would involve a great deal of additional plumbing and pipefitting, and then you'd likely need a larger compressor. The parallel-flow condenser will reduce head pressure in the system, reducing the engine's workload to run the compressor, while at the same time reducing temperature stratification of the air entering the radiator.

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Too many people who were born on third base actually believe they've hit a triple.