AC HELP NEEDED..

[CorvairGeek]

R4 compressors themselves are generally identical besides differences in coil clocking and possible manifold variances. Some coils are 9 o’clock and some are 12. That’s not the end of the world, though, to have to work around. You might have to lengthen the pigtail in some, but not all, cases. The original Delphi/Harrison compressors had some variances in suction/discharge port diameter, and some hoses had pilots while others didn’t. The new ones have a uniform manifold design and use different spacer seal combos to compensate for hose block differences. @CorvairGeek can likely elaborate on this better. Correct hose blocks are part of making new hoses so that’s not a dealbreaker either. I believe the A6s utilize either a 2 or 10 o’clock coil clocking, but the suction/discharge sizes, not to mention the manifolds themselves are the same. I’ll admit to not knowing these like the R4s and V5s, though.


The R4 pancake is an inferior design to really anything out there. That’s not to say that an individual compressor can’t go for many miles and work quietly, it does happen, but their design makes them more prone to not do either. The new ones have been built only by Comp Works/Four Seasons for like 25 years so there’s that monopoly. The A6 is solid, effective, just outdated compared with how designs improved over time like with Sandens or the Delphi/Harrison V5 and V7. They’re more expensive to deal with and very heavy to do what they do, but I would be open to resealing one. Even an R4 that didn’t have a lot of miles might be a candidate for a reseal, but if it had more than 80K, I’d junk it if it puked around the shell. I think puking around the shaft seal is more of an A6 attribute, but they’ve since come out with a better than OEM shaft seal for those.

Here is the sadistic GM sealing washer chart. I had to fix a leaking O-ring (the swtich port) on my R4 this year. Surprisingly, NAPA had a listing for that particular O-ring and the yellow and green (IIRC) sealing washers I needed.

Additionally, an old A6 compressor would have value to some people, as they can be resealed and are one of the best compressors ever made (IMHO). An old R4 is just scrap.

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[Howard Rogers]

thank you for the help... i guess i will roll the windows down like i used to...i dont use it enough to dump a ton of money in it..

 

[1987 GMC Jimmy]

Here is the sadistic GM sealing washer chart. I had to fix a leaking O-ring (the swtich port) on my R4 this year. Surprisingly, NAPA had a listing for that particular O-ring and the yellow and green (IIRC) sealing washers I needed.

Additionally, an old A6 compressor would have value to some people, as they can be resealed and are one of the best compressors ever made (IMHO). An old R4 is just scrap.

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Yeah, that’s the old “I’m installing a new compressor, but something’s not going right” cheat sheet. The 5/8 versus 3/4 suction port size difference is what I was alluding to, and then Taylor can see those five different hose blocks. Yes, I’d hold onto any A6, and there are a lot of rebuild videos on YouTube to help. I see where you’re coming from on the R4, although if it was a low mileage unit, I would be clingy just because of the Delphi/Harrison aspect of it. The Harrison R4 on my Jimmy died at like 183K, and there was just no way... I took it for a spin this morning, and the air’s solid. I’m never doing a white orifice tube again, though.

 

[AuroraGirl]

Oh, I might have 2-3 of the A6. At least they look the same. To me, someone who doesnt know much.

 

[mrburitto]

Here is one of the best write ups I have found for R12a btw. I don't sell it or anything, I just think it could save alot of people time and money if they had all facts. And its harmless to the ozone and environment which is a plus.

https://forum.ih8mud.com/threads/du...l-tm-aka-hydrocarbon-ac-refrigerants.1048595/

 

[Matt69olds]

If the system is closed up and still has refrigerate in it, get a can of oil charge (make sure it’s compatible with the existing refrigerate) and top off the system. If the system is empty, then definitely change the orifice tube, all the o-rings, etc. Vacuum the system, if it holds vacuum then you can be reasonably sure there are no leaks. if it’s empty, I’d do the 134a conversion.

 

[Ricko1966]

Flammable refrigerant and I do not mesh.I've heard the argument before about if you crash big deal blah blah. What I'm more concerned with is the car sitting in the attached garage with an evaporator leak or even a condenser leak getting lit off by a water heater.I worked at the dealership during the r12 phase out we didn't bring in any cars to do high dollar retrofit upgrade. We changed the orings the accumulated flushed vacuumed refilled with r134a to like 85 percent of what was listed for r12.I don't remember my gauge pressures.Latter in the game they changed their mind about the oprings as well unless they were new orings then they had to be 134. Back then Diy people were just using propane too brave, or too stupid for me. IDK just not something I'd do

 

[Goldie Driver]

Here is one of the best write ups I have found for R12a btw. I don't sell it or anything, I just think it could save alot of people time and money if they had all facts. And its harmless to the ozone and environment which is a plus.

https://forum.ih8mud.com/threads/du...l-tm-aka-hydrocarbon-ac-refrigerants.1048595/

I actually find this fascinating as with some minor mods it sounds like I could be back close to R12 goodness.

I'll have to ask some mechanics if they have heard of it.

The one independent shop I dealt with had not seen R12 in a while so going back to that through them was not an option.

Plus, if this stuff can be obtained almost as readily as 134 that is a huge benefit in case of leaks in my 40 year old system.

 

[mrburitto]

Flammable refrigerant and I do not mesh.I've heard the argument before about if you crash big deal blah blah. What I'm more concerned with is the car sitting in the attached garage with an evaporator leak or even a condenser leak getting lit off by a water heater.I worked at the dealership during the r12 phase out we didn't bring in any cars to do high dollar retrofit upgrade. We changed the springs the accumulated flushed vacuumed refilled with r134a to like 85 percent of what was listed for r12.I don't remember my gauge pressures.Latter in the game they changed their mind about the springs as well unless they were new springs then they had to be 134. Back then Diy people were just using propane to brave, or stupid for me. IDK just not something I'd do

You use so little gas that a fire is highly unlikely. You only use 30%-40% of what you would with 134a. So the only way it ignites is if, somehow, it ALL evacuates the system at once AND you happen to have a flame or spark right inside the car. I would have to do some math, but depending on the size of your garage im pretty sure that even if the whole system leaked out the concentration in an average garage would not be high enough for it to ignite. The information for the air concentration needed for it to be able to ignite is in that link I posted too.

I figured out I should only need about 3 of these tiny 6oz cans to fill the system in my 79 C30... Thats the equivalent of a few Black Cat firecrackers should it ever explode lol

 

[Itali83]

This is awesome information. I still have r12 in cans at my garage and have r12 in my 82 K10. I swear you can hang meat in that thing on fan speed 2 in the dead of summer. My suburban has been converted by previous owner to r134a and it sucks. The rear ac doesn’t cool at all and the front only barely. I’m going to go through the suburban and either use my r12 or try the r12a because then I won’t worry about running out or laying stupid money for more r12.
Ben