Once I get the interior squared away in the GS 350, I want to get the AC system functional. Better to convert to R134? If so, what kit should be used? Any other tips for those of us who would like fuctional AC systems? Thanks!!!
If you can find R12 anywhere, go with that. The AC system is designed for R12 properties and will freeze you out. R134 conversion is ok, the POA valve can be successfully recalibrated and the hoses need to be changed to barrier type hoses, but the system will still function very nicely. I recommend staying away from the cheapo CCOT conversion that eliminates the POA setup because the compressor cycles to control evaporator temp and pressure. It sounds dumb, and the the engine surges every time the compressor clutch turn on or off. The output temp also varies with evaporator variations. Lastly, the clutch face on the A6 compressor isn't very big, and therefore the cycling tends to wear the faces faster than normal. There are plenty of parts and knowledge around to support you!
Where would you get these "barrier style' hoses? I recently installed my AC (70GS) and installed new hoses from the parts place. Are those "barrier" style hoses that you mention? https://www.thepartsplaceinc.com/part/1970/skylark-gs-regal-gn/air-conditioning I've had my POA recalibrated and currently in process of finding a local shop to charge to R134A. Thanks, Nick
I went through mine and converted to R134a, recalibrated my own POA valve, new hoses etc. Couple of pointers: * R12 would be simpler, but getting quality R12 is near impossible (overseas sources are notoriously low-quality not pure R12) * A good R134a system will cool as well as R12, only it'll take 10-30 seconds to make cold air while R12 would do it almost immediately. * Spend the money and get a NEW compressor from a reputable source. The "remanufactured" ones aren't worth the box they come in - period! * Stock condenser will work OK, but really you'll want as big a "True Parallel Flow" condenser as you can possibly fit. R134a wants about a 30% bigger heat loss in the condenser, and a honking big modern design is the way to go. * www.ackits.com is where I've sourced all my AC gear for years, they don't sell or recommend junk. Good people, and their discussion forum is worth searching through.
They don't state one way or the other whether their hose is R134 rated or not. The last set I needed, I took to my local hydraulic store and they replaced the original hose with barrier hose. I was able to retain the original fitting but he crimps were different than original, however, I was ok with that.
I bought 4 cans of R12 & 2 cans of oil. Anyone know if there is an o-ring/ seal kit for stock compressor & components to seal everything up real well? I wouldn't want to lose my costly R12 into the air....
Most (if not all) hoses sold in the last 20 years is barrier hose. I don't see mention of recalibrating the expansion valve, it needs to be done too. R12 systems also froze-up , I noticed that the early evaporator enclosures (AKA suit case) didn't have thermostats in the to prevent freeze-up, the later do (late 70s). It is possible to get more air flow through the condensor by filling the gaps between the shroud and radiator, radiator and core support and the core support and condensor . There are big gaps in all those areas and there's no way the fan will draw enough air with all that leakage. I use 1/2 black foam pipe insulation to fill those gaps. It also helps to insulate the low side hose going from the POA valve and the compressor to prevent it from picking up heat.
one big word of advice if you are going to use a stock compressor. replace that bearing to the newer style. the old ones sling oil.
the bearing is the seal. a6 ones leak. there is a bearing you can swap out that was used on the later gm ones and it stops that leak. idr the name of the later gm compressor right off. its the shorter one gm trucks used in the 90s. from the factory gm said a small amount of oil leak is normal. that said if you want to not refill it every few years or have pag oil under you hood id swap. pretty simple swap. you do need a tool for the bearings. i found mine for 30 bucks. ebay.
