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1-PU70 03-08-2010 07:10 PM

AC POA Valve Update
 
1 Attachment(s)
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.

pickupman 03-08-2010 08:06 PM

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.

cparman 03-08-2010 08:43 PM

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

leddzepp 03-08-2010 08:52 PM

Re: AC POA Valve Update
 
Quote:

Originally Posted by cparman (Post 3848312)
The word of caution is that the A-6 compressors are not designed to be a clutch cycling type system.

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?

67vetteal 03-08-2010 09:51 PM

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

trucks72 03-08-2010 10:18 PM

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.

highperf4x4 03-09-2010 01:09 AM

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.

1-PU70 03-09-2010 10:48 AM

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.

mrein3 03-09-2010 02:14 PM

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.

highperf4x4 04-21-2010 12:22 AM

Re: AC POA Valve Update
 
Quote:

Originally Posted by 1-PU70 (Post 3849491)
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.

Have you done anything with it yet?

Andy4639 04-21-2010 03:39 AM

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

HuggerCST 04-21-2010 10:37 AM

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.

1-PU70 04-21-2010 01:31 PM

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.

CharlieBrown 04-21-2010 02:57 PM

Re: AC POA Valve Update
 
so..no one likes this setup?

highperf4x4 04-21-2010 03:19 PM

Re: AC POA Valve Update
 
Quote:

Originally Posted by CharlieBrown (Post 3933076)
so..no one likes this setup?

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

highperf4x4 04-21-2010 03:20 PM

Re: AC POA Valve Update
 
Quote:

Originally Posted by 1-PU70 (Post 3932928)
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.

Ok, I'll be waiting for the info.

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

CharlieBrown 04-21-2010 03:55 PM

Re: AC POA Valve Update
 
well

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

Tkmadone 04-21-2010 03:59 PM

Re: AC POA Valve Update
 
I used it on my '67 and it works great. It doesn't really cycle but it cools great.

1-PU70 04-21-2010 06:25 PM

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.

leddzepp 04-21-2010 06:33 PM

Re: AC POA Valve Update
 
Quote:

Originally Posted by 1-PU70 (Post 3933403)
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.

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.

Andy4639 04-21-2010 10:28 PM

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:

highperf4x4 04-21-2010 11:56 PM

Re: AC POA Valve Update
 
Great! Now I'm really unsure!

mosesburb 04-23-2010 06:03 AM

Re: AC POA Valve Update
 
Quote:

Originally Posted by 1-PU70 (Post 3933403)
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.

Quote:

Originally Posted by leddzepp (Post 3933413)
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.

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.

leddzepp 04-23-2010 12:46 PM

Re: AC POA Valve Update
 
Quote:

Originally Posted by mosesburb (Post 3936127)
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.

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

69sixpackbee 04-23-2010 01:05 PM

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


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