AC POA Valve Update
 

Has any one changed there AC from a POA valve to a new cycling system valve. I was wondering if it is worth the effort and how well does it cool? My system was converted to 134 years ago and never really cooled that great.Here is a pic of the new valve Im talking about.

Re: AC POA Valve Update
 

I have it on my 71 and seems to work fine. Dont know the workings of it but have not had any problems out of it.

Re: AC POA Valve Update
 

had one on my Chevelle, and it worked great. I think that old air products sells a kit that would convert our trucks to a modern accumulator/orifice tube setup. If you are not all back together, I would think this would be a great way to go. The word of caution is that the A-6 compressors are not designed to be a clutch cycling type system. As a side note i have one customer that we converted to a clutch cycling system, and it is 35 degrees on a hot NE Florida day. Did the conversion a few years ago

Re: AC POA Valve Update
 

This is why I did not convert the original POA on my system. I have R-134 and it cools great. Have you checked your pressures?

Re: AC POA Valve Update
 

Check out AutoACForum.com . Also, you can Google your questions. Al W.
http://www.autoacforum.com/categories.cfm?catid=2

Re: AC POA Valve Update
 

I have used alot of those. They will not stick like a factory one. They are not a cycling valve though. The wiring on it just shuts off the comp. if the pressure gets low. So it will not pump if there is not enough freon in it. I never wire mine up. I think it looks bad in the truck.

Re: AC POA Valve Update
 

Actually I found a local guy that takes the guts out of the POA valve and installs an orifice for 134 and a high pressure switch to make it cycle. That's the route I'm going. It will look almost factory with the addition of a wire connection on the POA valve.

Re: AC POA Valve Update
 

Yes the accumulator/orifice tube setup would be the way to go but I dont feel like tearing my AC apart right now. It does work but doesn't cool very good. It works good enough to cool if its raining or at night, but on a sunny day not so good. I read that the POA valve could be adjusted for 134 on a bench with shop air but I cant find any one local who knows about it. So I thought that the POA update would be a simple way to go.

Re: AC POA Valve Update
 

I would leave the POA in there, adjust it properly for R134a, and leave it.

To learn how to adjust it, click to:
http://www.autoacforum.com/messagevi...&threadid=7567

I wish I had a nickle for every time I've posted that link when somebody said their R134a conversion doesn't cool properly.

Re: AC POA Valve Update
 

Have you done anything with it yet?

Re: AC POA Valve Update
 

Just do as I did and it works great. Just stick the screen in the lower line.

http://216.77.188.54/coDataImages/p/...0/DSC00353.JPG

http://216.77.188.54/coDataImages/p/...0/DSC00352.JPG

Re: AC POA Valve Update
 

I have one on mine and it cools great with R-12. If you use R134 you really need a condensor made for R134, or at least more air flow across the condensor at idle, or low speeds.

Re: AC POA Valve Update
 

Well I decided to get my POA adjusted for 134. There is a place in Tampa Clasic Auto Air about 40 minutes away. I talked to a guy there and he talked me into having my POA rebuilt and adjusted for 134. Im having my system evacuated today and taking the POA and the dryer out tonight. I will be going to Tampa Fri, so I will keep you posted.

Re: AC POA Valve Update
 

so..no one likes this setup?

Re: AC POA Valve Update
 

I don't know. I'm confused now. :lol:

Re: AC POA Valve Update
 

Ok, I'll be waiting for the info.

Don't forget to tape off anything that exposes the system to the atmosphere!

Re: AC POA Valve Update
 

well

I just ordered the kit..guess I'll find uot

Re: AC POA Valve Update
 

I used it on my '67 and it works great. It doesn't really cycle but it cools great.

Re: AC POA Valve Update
 

The reason Im keeping the POA is because I read that the A6 is ment to run constantly and not cycle. Im worried that if Im driving all day on a long trip it might screw up the compresser cycling all day.

Re: AC POA Valve Update
 

This is why I retained the factory POA and used the procedure mrein3 described above to adjust it. If you change over to the orifice tube, I would refrain from hooking up the cycling switch as trucks72 stated above.

Re: AC POA Valve Update
 

Well my luck with the old A-6 compressor's was not worth the time to even borther with it. Get a aftermarket compressor and be done. I bought 4 that's right 4 A-6 compressor over about a 10 year peroid and didn't last more than 2 years on any of them. They were all 134-A suposedly to! I went over a year without ac.
Aftermarket compressor with cycling has been on the truck now for 3 years and no problems and haven't charged it since the install.;):metal::chevy:

Re: AC POA Valve Update
 

Great! Now I'm really unsure!

Re: AC POA Valve Update
 

A6 compressors can be used with a clutch cycling switch. Air conditioning systems using the A6 compressor in the late seventies and early eighties came from the factory in CCOT (Clutch Cycling Orifice Tube) systems.

It used to be that the A6 was the horsepower hog that never died, but in my years of selling parts I found that their reputation is not as stellar anymore (they are still HP hogs). The compressor is still an extremely rugged and durable design, but the manufacturing and remanufacturing of these compressors has diminished their reputation.

For years I would only sell new compressors. Reman units were (and most still are) junk. I sold several new A6 units over the years, but around 94-95ish most of the units I sold (new GM units) came back with either front seal problems or clutch problems. One customer needed his vehicle and I couldn't get another new A6 for a few days, so I got him a Delco reman unit. That one lasted great. After I switched out most of the 94-95 units for remans I was able to keep those away for a long time. The cost of the new units was ridiculous and the Delco reman units were cheaper so it was easier to sell those especially when they seemed to outlast the new ones (defies all logic--maybe the manufactuing of new ones was transfered from GM to an outside vendor or something).

The problem with the reman units (Delco or other brands) is they take a compressor and clutch that has been reman'd several times already and reman it again and expect a good sevice life out of it. I had several compressors come in that I could not adjust the proper air gap on the clutch because the friction surfaces of the clutch had been resurfaced so many times. Whoever reman'd the units for Delco seemed to hold their tolerances tighter than the Joe-Q rebuilder, but I did have issues with a few of theirs over the years.

So to make a long story a bit longer, it is safe to cycle the clutch on the A6 provided it is in good condition and the system is properly charged (GM did it for years). If the clutch is cycling enough to damage the clutch then either the system is low on refrigerant (this will kill a compressor that runs constantly also), the system has way too much high side pressure (also will kill a constant running comp) or the outside ambient air temp is low and you should have your windows down instead of running the A/C. I also agree with Andy4639 that if you are not going for originality, scrap the A6, go with a Sanden/Sankyo/Zexel and enjoy the horsepower that is not rquired to spin the compressor and enjoy the durability of a more modern design.

Re: AC POA Valve Update
 

Thanks for the info :metal: I also have had the experiences that Andy had. My latest A6 seems to be holding on. I am keeping my fingers crossed. I was thinking of using one of these next time my compressor takes a dump: http://cgi.ebay.com/ebaymotors/1972-...Q5fAccessories

Re: AC POA Valve Update
 

I am using the original POA (readjusted) with a Sanden compressor.

A-6 is the way to go but for my money I kept the POA. That is still the best way to go.
http://img.villagephotos.com/p/2004-2/638601/POA_1.jpg

Re: AC POA Valve Update
 

Sanden: Smaller, lighter, more efficient and much more durable. Win-win.

Re: AC POA Valve Update
 

I bought a Haynes A/C Manual and learned to do my own A/C work, to avoid constant trips to the A/C shop. My 72 Cheyenne has the same A6 compressor as when I bought it in 2003. I had the POA adjusted for 134a, new dryer and expansion valve and my A/C has worked fine in south Florida for over 10 years. My 1972 Cutlass, same set-up but also with a cross flow condenser pumps out 30 degree air from the vents. Also, same A6 compressor as when I bought it in 2006, and it hadn't been replaced in the 4 years the previous owner had the car.

I have a 1970 Bonneville that I am rebuilding. Classic Auto Air in Tampa suggested I get a rebuilt A6 right before I install it. The seals have a tendency to leak if they sit on the car or on the shelf and not used. Even a brand new seal can go bad and leak if the system is not charged and used.

Re: AC POA Valve Update
 

30 degree air in South Florida? Did you mean 40 degree? Maybe a bad thermometer?

A6 compressor is big enough to cool a small house and it's the only compressor I've ever seen with it's own oil pan and oil pump. Some shoddy re-builders have given others the impression that they are not good, but really they are very good.

I just think their day has came and went, too big and too heavy with a small clutch diameter that makes for a weak clutch that does not hold up well on a cycling system.

I have a question for you that I've tried to research to no avail. Is there a different expansion valve for 134A?

Re: AC POA Valve Update
 

Not that I know of. A properly R134a adjusted POA will keep the evaporator core cold

Re: AC POA Valve Update
 

Not sure who says an A6 can't be used cycling. I had a '77 and a '79 Pontiac Bonneville with A6 compressors and pretty sure both had cycling systems. The '77 had almost 300,000 miles on the original compressor. Ford also used them. We had a '79 LTD that had an A6. I don't know if it was cycling or not.

I have installed a few of these kits with no big issues. Put on a '71 C10 and a '67 Firebird. Both still going fine as far as I know.