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Replace a working R12 system with Duracool [message #218271] Wed, 14 August 2013 07:47 Go to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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My dash AC works well. It has R12 in it. Under the age old saw of 'if it works....don't fix it', it goes against the grain to change it. However, is there enough improvement going to Duracool to justify pulling off the R12 and replacing it with Duracool?

Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: [GMCnet] Replace a working R12 system with Duracool [message #218274 is a reply to message #218271] Wed, 14 August 2013 07:57 Go to previous messageGo to next message
Emery Stora is currently offline  Emery Stora   United States
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If it is cooling well I would leave it alone. When you find that it needs refrigerant to be added then I would consider replacing the Freon 12 with Duracool.

It is estimated that Duracool will give about 10% improvement in cooling.

For those that find that they have to add perhaps 1 can of 12 ounces of Freon R12 a year due to a slow leak, changing to Duracool might stop that leak. The propane molecule is much larger than the Freon so I had originally found that my slow leak past the clutch seal went away after I installed Duracool and I went 6 years before I had to top it up with about 3 ounces of Duracool.

Emery Stora

On Aug 14, 2013, at 6:47 AM, Kerry Pinkerton <Pinkertonk@MCHSI.com> wrote:

>
>
> My dash AC works well. It has R12 in it. Under the age old saw of 'if it works....don't fix it', it goes against the grain to change it. However, is there enough improvement going to Duracool to justify pulling off the R12 and replacing it with Duracool?
> --
> Kerry Pinkerton
>
> North Alabama, near Huntsville,
>
> 77 Eleganza II, "The Lady", 403CI, also a 76 Eleganza being re-bodied as an Art Deco car hauler
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Re: Replace a working R12 system with Duracool [message #218302 is a reply to message #218271] Wed, 14 August 2013 11:56 Go to previous messageGo to next message
Cadillackeeper is currently offline  Cadillackeeper   United States
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My 12 systems have SUVA right on the 12.Almost a can and a half in the UAV on top.
I agree to leave it unless its low to add.


77 455 Elaganza II and 67 Animal, Built 500 Powered Eldo
Re: [GMCnet] Replace a working R12 system with Duracool [message #218306 is a reply to message #218271] Wed, 14 August 2013 12:05 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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Relative to R12? Nah, marginal. Relative to R134a? Yeh, substantial.

--johnny
'76 23' transmode norris
'76 palm beach

--------------------------------------------
On Wed, 8/14/13, Kerry Pinkerton <Pinkertonk@MCHSI.com> wrote:

Subject: [GMCnet] Replace a working R12 system with Duracool
To: gmclist@temp.gmcnet.org
Date: Wednesday, August 14, 2013, 12:47 PM



My dash AC works well.  It has R12 in it.  Under
the age old saw of 'if it works....don't fix it', it goes
against the grain to change it.  However, is there
enough improvement going to Duracool to justify pulling off
the R12 and replacing it with Duracool?
--
Kerry Pinkerton

North Alabama, near Huntsville,

77 Eleganza II, "The Lady", 403CI, also a 76 Eleganza being
re-bodied as an Art Deco car hauler
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Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: Replace a working R12 system with Duracool [message #218314 is a reply to message #218271] Wed, 14 August 2013 13:06 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
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Kerry Pinkerton wrote on Wed, 14 August 2013 07:47

My dash AC works well. It has R12 in it. Under the age old saw of 'if it works....don't fix it', it goes against the grain to change it. However, is there enough improvement going to Duracool to justify pulling off the R12 and replacing it with Duracool?

Well, head pressure in the compressor will be higher with R12 than with Duracool, so you will notice a slight drain in engine power when the AC is on. Head pressure is low enough with duracool that while there may be a very minor drain in power,you don't even notice it. I went from R12 to Duracool. Noticeable drain in power especially at idle until I switched. Not noticeable anymore. Motor doesn't even know it's there.
Just my observation.


Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: [GMCnet] Replace a working R12 system with Duracool [message #218319 is a reply to message #218314] Wed, 14 August 2013 13:31 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Yes, and you get cooling at idle with Duracool whereas you don't with R12. And you engine RPM doesn't drop down as much when you stiop.

Emery Stora
On Aug 14, 2013, at 12:06 PM, Larry wrote:

>
>
> Kerry Pinkerton wrote on Wed, 14 August 2013 07:47
>> My dash AC works well. It has R12 in it. Under the age old saw of 'if it works....don't fix it', it goes against the grain to change it. However, is there enough improvement going to Duracool to justify pulling off the R12 and replacing it with Duracool?
>
> Well, head pressure in the compressor will be higher with R12 than with Duracool, so you will notice a slight drain in engine power when the AC is on. Head pressure is low enough with duracool that while there may be a very minor drain in power,you don't even notice it. I went from R12 to Duracool. Noticeable drain in power especially at idle until I switched. Not noticeable anymore. Motor doesn't even know it's there.
> Just my observation.
> --
> Larry :)
> 78 Royale w/500 Caddy
> Menomonie, WI.
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Re: [GMCnet] Replace a working R12 system with Duracool [message #218325 is a reply to message #218319] Wed, 14 August 2013 14:02 Go to previous messageGo to next message
jtblank is currently offline  jtblank   United States
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Wouldn't another benefit of switching to Duracool, and it's less parasitic drag on the engine, result in better MPG?

John Blankenship '76 Palm Beach Tulare, CA
Re: [GMCnet] Replace a working R12 system with Duracool [message #218327 is a reply to message #218274] Wed, 14 August 2013 14:27 Go to previous messageGo to next message
George B. is currently offline  George B.   United States
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I had a new under-dash unit installed re-using most of the original R12 components except the original evaporator was bypassed. System worked great! Now two-years latter the cooling has declined so I looked and saw the bubbles in the sight glass so it appears the R12 is low.

From what it sounds like I should now consider changing over to Duracool. I think I remember reading some instructions on how to change over but seemed the instructions were incomplete. Is it a DIY job and what tools guages are required or best left to a professional?


George Butts Las Vegas Nevada 73 "Custom 26' Q" & 76 23' Birchaven 71 Honda 600 Coupe & 01 Tracker Toads
Re: [GMCnet] Replace a working R12 system with Duracool [message #218332 is a reply to message #218327] Wed, 14 August 2013 15:08 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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If you still have R12 in the system you can just bleed it off by depressing the Schrader valve (tire core valve) located in the LOW pressure line. The HIGH pressure line is the line that has the switch in it with wires going to the clutch and which leads to the receiver/drier.

It is against the rules to bleed off R12 to the atmosphere. If that bothers you then you can go to an air conditioner shop and have them recover the R12 and pull a vacuum on the system. With the high cost of R12 they should do this for you free if you give them the R12. If they want to charge you then go someplace else or just bleed it off.

You should have a gauge set that will fit on your low pressure line and high pressure line. If you system is working well you don't even have to use the high pressure side of the gauge set.

You will need a hose that connects to the R134a type fitting on the top of the can and an R12 fitting to connect to the middle of your gauge set. I bught that hose at Bennet Cycle when I get my Duracool. Whoever sells you the Duracool should have that short hose available.

If the hose from the left side of the gauge set is connected to the low pressure hose of you system, you connect the can by using the short hose to the center of the gauge set and open the valve on the left of your gauge set.

For Duracool feed the liquid into the system -- that is turn the can upside down. This is the opposite of R12 where you leave the can upright and feed the vapor into the system After you have part of a can in you should start up your air conditioner and put the balance of the can in. The pressure from the first half of a can will be enough to close the switch in the high pressure line and engage the compressor clutch. With the engine running and the air conditioner on, close the valve on the left of the gauge set and remove the empty can. Put on a new can and then open the valve and feed the second can into your system. Repeat this for the third can.
Even with a second evaporator in your system three six ounce cans of HC12a (Duracool) should be just about right.

To check your charge run your engine at 1500 rpm and check the low side pressure (the left hand valve on the gauge set should be off (clockwise). Read the gauge. It should show about 20 to 25 psi. On a really hot day it might even show 30 psi. That is about right. On a 80 degree day when my radiator isn't yet hot mine will read 20 psi. When the radiator and the condensor mounted in front of the radiator get hot then the pressure will go higher.

Some people have just ignored the use of a gauge set and just got a hose from the can to the LOW pressure line and fed in three cans and it has worked well for them.

By he way, the bubble sight gauge in the top of the drier is useless with Duracool. That only works with Freon R12.

Let me know if you have any questions.

Emery Stora

On Aug 14, 2013, at 1:27 PM, GEORGE BUTTS wrote:

>
>
> I had a new under-dash unit installed re-using most of the original R12 components except the original evaporator was bypassed. System worked great! Now two-years latter the cooling has declined so I looked and saw the bubbles in the sight glass so it appears the R12 is low.
>
> From what it sounds like I should now consider changing over to Duracool. I think I remember reading some instructions on how to change over but seemed the instructions were incomplete. Is it a DIY job and what tools guages are required or best left to a professional?
> --
> George Butts
> Apple Valley Calif.
> 73 "Custom 26 Q"
> _______________________________________________
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Re: [GMCnet] Replace a working R12 system with Duracool [message #218333 is a reply to message #218325] Wed, 14 August 2013 15:09 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Yes, but with the low gas mileage you get with the GMC I don't think you would be able to measure it.

Emery Stora

On Aug 14, 2013, at 1:02 PM, John Blankenship wrote:

>
>
> Wouldn't another benefit of switching to Duracool, and it's less parasitic drag on the engine, result in better MPG?
> --
> John Blankenship
> '76 Palm Beach
> Tulare, CA
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Re: [GMCnet] Replace a working R12 system with Duracool [message #218341 is a reply to message #218333] Wed, 14 August 2013 15:56 Go to previous messageGo to next message
ernie is currently offline  ernie   United States
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Hi Emery,
Your explanations are really clear. Can you do the same thing for converting to Duracool on a 1975 GMC Eleganza II with a standard AC ?
ernie


ernie garcia
1975 eleganza II
ellensburg, wa
Re: [GMCnet] Replace a working R12 system with Duracool [message #218343 is a reply to message #218341] Wed, 14 August 2013 16:27 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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or

bleed it off
add 3 cans of duracool
and
drive off
http://gmcmotorhome.info/heat.html#duracool

(thats what emery does :>)

gene



On Wed, Aug 14, 2013 at 1:56 PM, ernie garcia <ernie-garcia@charter.net>wrote:

>
>
> Hi Emery,
> Your explanations are really clear. Can you do the same thing for
> converting to Duracool on a 1975 GMC Eleganza II with a standard AC ?
> ernie
> --
> ernie garcia
> 1975 eleganza II
> ellensburg, wa
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--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
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Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] Replace a working R12 system with Duracool [message #218344 is a reply to message #218341] Wed, 14 August 2013 16:30 Go to previous messageGo to next message
ljdavick is currently offline  ljdavick   
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Ernie,

It would be exactly the same.


Larry Davick
Fremont, California
A Mystery Machine
'76 (ish) Palm Beach

----- Original Message -----
From: "ernie garcia" <ernie-garcia@charter.net>
To: gmclist@temp.gmcnet.org
Sent: Wednesday, August 14, 2013 1:56:17 PM
Subject: Re: [GMCnet] Replace a working R12 system with Duracool



Hi Emery,
Your explanations are really clear. Can you do the same thing for converting to Duracool on a 1975 GMC Eleganza II with a standard AC ?
ernie
--
ernie garcia
1975 eleganza II
ellensburg, wa
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Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
Re: [GMCnet] Replace a working R12 system with Duracool [message #218346 is a reply to message #218341] Wed, 14 August 2013 16:41 Go to previous messageGo to next message
Emery Stora is currently offline  Emery Stora   United States
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Just the same. A second evaporator only uses vapor so three cans is about the right amount whether it is a standard system or one with an additional evaporator.

Emery Stora

On Aug 14, 2013, at 2:56 PM, ernie garcia <ernie-garcia@charter.net> wrote:

>
>
> Hi Emery,
> Your explanations are really clear. Can you do the same thing for converting to Duracool on a 1975 GMC Eleganza II with a standard AC ?
> ernie
> --
> ernie garcia
> 1975 eleganza II
> ellensburg, wa
> _______________________________________________
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Re: Replace a working R12 system with Duracool [message #218354 is a reply to message #218271] Wed, 14 August 2013 17:34 Go to previous message
Cadillackeeper is currently offline  Cadillackeeper   United States
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Careful on taking it somewhere!!!Unless you are putting in R-12 or changing to 134 or just topping off an R-12 with Dupont Suva which , yes is a form of 134.Most of the Duracool or ????????? is illeagal in our Old Stuff!!!Trust me as I have had the same car since 1979!!! Not the same one but the same model.The 1967 Eldorado with a built up 1970 Eldorado engine I drive now I have had since 2003!I hope for it to be my last.Same for the UAV.

http://www.epa.gov/ozone/snap/refrigerants/hc-12a.html


77 455 Elaganza II and 67 Animal, Built 500 Powered Eldo
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