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Tired Of Sweating In The GA Summers

Starfighterpilot

By Starfighterpilot,
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Starfighterpilot Newbie

Starfighterpilot

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I'm getting old and want to enjoy my creature comforts, and not sweat my *ss off driving the Starion in the hot and humid Georgia summers anymore.

 

Harbor Freight has a A/C system vacuum pump on sale for about $50.00 and the gages for about the same price.

 

It usually costs me around $85.00 every other summer to have the OEM A/C System pumped down, checked for leaks (never had any), dryer changed and the system repressurized with Freon 134. It appears that over a 2 year period that the F 134 SSSSSSLLOOOOWLY leaks through the MITSU OEM Freon 12 hoses because of osmosis.

 

So, I made up my mind to convert the OEM Freon 12 A/C System over to Freon 134.

 

I am going to replace all of the OEM Freon 12 A/C Hose material with Freon 134 material reusing the OEM hose end fittings.

 

Plus I want to replace all of the Freon 12 o-rings with 134 compatible material. The '88 part catalog shows 9 o-rings total of three different sizes in the engine house, however it does not show what the o-ring sizes are.

 

Does any one know what o-ring material to use, the sizes, and the number of each size in order to replace all the o-rings in the engine house. I'm not going to replace the two o-rings under the dash by the evaporator. Too much of a PITA.

 

I already have a brandy new F 134 compatable dryer waiting to be installed.

 

Also, because of the different chemical composition between Freon 12 and 134A which effects the heat transfer capability between the two,, how much Freon 134A with compressor oil should I add; ballpark estimate. I'll tweek it in with the compressor discharge pressure gauge.

 

Thanks In Advance

 

KEN

 

Edit - Correct me if I'm wrong, but I do not believe that the expansion valve has to be replaced for the conversion.

Edited by Starfighterpilot
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gofastredstar Newbie

gofastredstar

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Hey guys, while I am no expert, I resently got my a/c working. But I took it to a shop to have all the pieces flushed. I understand this to be necessary if the components have been open for a long time. And I also had new 134a compatable hoses made. It now blows pretty cold.
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VICE Newbie

VICE

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How hot does it get in GA? Cuss in FL it gets pretty darn hott and humid sweaty believe me.. :sweatingitout: My A/C blew cold till a couple years ago the clutch in the compressor broke I got a remanufactured compressor from some Advance Auto store and a new expansion valve wit a R12 recharge since and I've had nice A/C it just feels like the other compressor was colder? Or could it be some kind of new Freon they use for the R12 that's supposed to be not as polluting or something.. I always believed the original R12 set up is better, colder but I dunno I'm no expert.. Oh did I mention I have a toggle switch to turn on the compressor along wit the 3rd fan infront of the radiator.. :winking0013: Edited by VICE
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ucw458 Grand Master

ucw458

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I'm getting old and want to enjoy my creature comforts, and not sweat my *ss off driving the Starion in the hot and humid Georgia summers anymore.

 

Harbor Freight has a A/C system vacuum pump on sale for about $50.00 and the gages for about the same price.

 

It usually costs me around $85.00 every other summer to have the OEM A/C System pumped down, checked for leaks (never had any), dryer changed and the system repressurized with Freon 134. It appears that over a 2 year period that the F 134 SSSSSSLLOOOOWLY leaks through the MITSU OEM Freon 12 hoses because of osmosis.

 

So, I made up my mind to convert the OEM Freon 12 A/C System over to Freon 134.

 

I am going to replace all of the OEM Freon 12 A/C Hose material with Freon 134 material reusing the OEM hose end fittings.

 

Plus I want to replace all of the Freon 12 o-rings with 134 compatible material. The '88 part catalog shows 9 o-rings total of three different sizes in the engine house, however it does not show what the o-ring sizes are.

 

Does any one know what o-ring material to use, the sizes, and the number of each size in order to replace all the o-rings in the engine house. I'm not going to replace the two o-rings under the dash by the evaporator. Too much of a PITA.

 

I already have a brandy new F 134 compatable dryer waiting to be installed.

 

Also, because of the different chemical composition between Freon 12 and 134A which effects the heat transfer capability between the two,, how much Freon 134A with compressor oil should I add; ballpark estimate. I'll tweek it in with the compressor discharge pressure gauge.

 

Thanks In Advance

 

KEN

 

Edit - Correct me if I'm wrong, but I do not believe that the expansion valve has to be replaced for the conversion.

 

 

I am an AC guy and have been doing it for many years. First the easy question. R134a and R12 are very similar in the way they work so an expansion valve replacement is not nessecary.

 

You will want to replace the filterdrier with a 134a unit.

 

To get better performance you want to flush the system because the oil for R12 and the oil for 134a DO NOT mix. The oil needs to be hydroscopic,(may have mispelled that) Basically the freon dissolves the oil and carries it throughout the system to lube all the moving parts and make sure the oil doesn't pool in one spot. The mineral oil used in R12 systems is not compatable with 134a. If you have had leaks in the past you can get away with just adding 8oz of 134 oil and charging the system. (oil comes out when you have a leak, not all of it but a fair amount.

 

 

Now here's the big conspiracy.

You do not have to change your seals and hoses to convert over to R134a. Everyone tells you to convert those parts because is you are looking to put R134a into your system then the R12 must have leaked out somewhere. Basically because of enviromental regulations they tell you to convert your system because they don't want refrigerant leaking into the atmosfere. Find your leak. They make leak finders that help you find the leak with the aid of a blacklight. Just put in the UV dye and use a blacklight to find the leak. Once that's fixed add your R134a and your AC will work fine.

 

If you don't belive the R134a seal gimic is a hoax then use my other car as an example. My 67 Ford has had R134a in it for 10 years with no problems. The only things on that AC that were not installed by Ford in 1967 and a new filterdrier and a replacement high pressure hose. The high pressure hose was cracked and leaked that is the only reason I replaced it and I didn't use R134a compatable hose. I have never once had a problem with that AC

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Starfighterpilot Newbie

Starfighterpilot

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Now here's the big conspiracy.

You do not have to change your seals and hoses to convert over to R134a. Everyone tells you to convert those parts because is you are looking to put R134a into your system then the R12 must have leaked out somewhere. Basically because of enviromental regulations they tell you to convert your system because they don't want refrigerant leaking into the atmosfere. Find your leak. They make leak finders that help you find the leak with the aid of a blacklight. Just put in the UV dye and use a blacklight to find the leak. Once that's fixed add your R134a and your AC will work fine.

 

If you don't belive the R134a seal gimic is a hoax then use my other car as an example. My 67 Ford has had R134a in it for 10 years with no problems. The only things on that AC that were not installed by Ford in 1967 and a new filterdrier and a replacement high pressure hose. The high pressure hose was cracked and leaked that is the only reason I replaced it and I didn't use R134a compatable hose. I have never once had a problem with that AC

 

Right you are Jeff. :thumbsup:

 

I copied the below from the EPA's Website. Read the below!! :read: It has some good info about converting A/C Systems from R 12 to R 134A.

http://www.epa.gov/ozone/title6/609/techni...trguid.html#oem

 

I do not have to change out the hoses or the o rings, unless I have leakers. :hmm3grin2orange: :D

 

This will save me some BIG BUCKS. :hmm3grin2orange:

 

For What It's Worth.

 

KEN

Edited by Starfighterpilot
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newquest86 Newbie

newquest86

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im also trained and certified for ac retrofits to r 134a you dont have to use special o rings just make sure they are new and oil them dont install them dry always change the receiver drier when doing a retrofit and also change it if it is more than 5 years old the oil i use is estercool oil and it is compatible with r 12 mineral oil yes it mixes pag oil dosent mix with mineral oil if you are doing a total flush of entire system you really cant do it unless you remove all components out of the car think about it how are you gonna get all the oil out ?the way i do it is try to get as much oil out of the system as you can change the receiver drier all o rings add 8 oz of estercool oil i use the one with the dye in it makes it easier to find leaks in the future evacuate the system for 45 minutes to remove all moisture and then add r 134 a i have a chart you use less r 134a than 12 because it works at higher pressures for instance a 1986 conquest calls for 25.8 ounces of r 12 so if using r 134 a you will use 22.4 ounces but dont over charge 2 ounces too much will give you a higher duct temperature 2 ounces too little will give you a higher duct temperature all the retrofits i ever did especially on gm cars i did this way and i had duct temperatures around 40 degrees some down to 37 i know the 88 and 89 cars take more refridgerant so if somebody wants to pm me with the factory charge i will post the r 134 a amount to use up here for everybody

 

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newquest86 Newbie

newquest86

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what are your duct temperatures at idle ? and also r 134 a will leak after 5 years or so on any car so remember these cars are how old ? hmmmmmm....... hoses are weak and all o rings are weak also compressor seals are weak receiver drier has a desicant bag in it it removes moisture it can only absorb so much then it is no good the more you change the longer it will last oh and dont forget the valve cores in the high and low side charging ports i am just doing my retrofit and found the high side valve cap locktited on after i got it off i removed the core and it was loose so their fix was to seal the cap on ? someone shouldnt have a set of tools LOL ! Edited by newquest86
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Shelby Newbie

Shelby

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hint about the air driven harbor freight vacum pumps the are not a true pump they are more of a sypher style,, they also can not draw down a system to 28-29 inches , how ever this is not a great problem if the system your working on had freon in it and the system was not open for an extend'd time , but they are not any where near as good as a real vacum pump ,i'l also recomend the easteroil over paq oil for an older car that was ran with R12

 

newer orings are made from a better grade of rubber and will not get hard nearly as quick as the older style back rubber orings , the oring color desinates the orings dia as much as any thing,the old blk orings some times are a bit on the thin side so a thicker wall'd oring may give a better seal

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Starfighterpilot Newbie

Starfighterpilot

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Thanks guys, for the additional input.

 

On second thought to do this properly I guess I should replace the 21 year old hoses and o-rings; even if they are not leaking Freon 134A now. That way I will not have to tear into the AC system again.

 

I'm getting dangerous again. My Starion is a 5 speed manual.

 

I have been looking at the '88 Parts Catalog (page 24-52) and the Shop Manual and noticed that the Starquest's with auto trannys have a side AC Condenser (part nos. 29, 31, 32, 33 and 37) and a larger secondary radiator fan (Parts Catalog, page 7-23, Part nos. 27, 28, 29, 30, 31, 32) to help the AC System over come the air flow reduction (or increased air temps) going across the Main AC Condenser/Radiator caused by the Auto Tranny ATF Cooler.

 

Note: the '88 Parts Catalog, page 24-52 & 53, Part no. 10, AC Condenser Fan Assembly does not make a distinction between the manual and auto tranny's. So, I am assuming that they are the same.

 

Would installing a used, leak free, Side AC condenser and auto tranny secondary radiator fan assembly(increasing the heat transfer surface area) make up for the reduced heat transfer capacity of the R134A verses the R12?

 

Or am I just blowing smoke out my rectal orifice.

 

Has anyone done this?

 

Thanks for any input.

 

For What It's Worth.

 

KEN

Edited by Starfighterpilot
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craig87 Newbie

craig87

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not worth the effort to install the side condenser. you will have higher vent temps with the 134a it just the nature of the refrigerent its not as good at heat transfer as 12 hell propane is a better refrigerent then both but not worth the risk of BOOM. like the poster above dont rig your fan to on at all times if you drive you low pressures to low all the time it will have high vent temps. as far as the barrier hose debate I would change them just because i don't like doing the same job twice.
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vbrad511 Newbie

vbrad511

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I did the 134 swap on my 87 back in the mid 90's. I had to recharge it every year, but the system had a leak (the r12 had all leaked out when I got the car). But at $5 a can it was acceptable to me (I was too lazy to hunt for a leak, and they didn't have the florescent dye stuff OTC then either). When I bought my 88 the PO had deleted all the AC stuff so I swapped in my 87 system complete, minus the new drier. While I had it apart I took all the under-hood orings I could find out and ran them to an AC shop here in town and matched them all up with new one (I think they were green). Put it all together in '03 and I've had to recharge it just once since then.
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Quest4life Newbie

Quest4life

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Why does everyone feel the need to switch? 12 is colder then 134 and less apt to leak. 12 is still easily obtained al over ebay and if you keep your system free of leaks it is not that costly. Way cheaper then any conversion. You can get certified for autos online very easy. Just a test. then you can buy 12. Regaurdless of 12 or 134 you need to know what you are doing. Just a thought.
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Starfighterpilot Newbie

Starfighterpilot

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Why does everyone feel the need to switch? 12 is colder then 134 and less apt to leak. 12 is still easily obtained al over ebay and if you keep your system free of leaks it is not that costly. Way cheaper then any conversion. You can get certified for autos online very easy. Just a test. then you can buy 12. Regaurdless of 12 or 134 you need to know what you are doing. Just a thought.

 

WOW!!!!!!!!!!!!!!!!

 

You are right!!!!!!!

 

HHHHHHHHHHHHHMMMMMMMMMMMMMMMMMM!!!!!!!!!!!!!!!!!!!!!!!!!

 

Here is the link.

 

http://cgi.ebay.com/ebaymotors/R12-REFRIGE...essoriesQ5fGear

 

For What It's Worth.

 

KEN

 

Edit - if you order the R-12 this comes up:

Federal Law provides that ONLY the following can purchase Refrigerants.

 

(1) E.P.A. Certified Refrigerant Technicians under Section 608 or 609 of the United States Clean Air Act.

 

(2) Purchasers of Refrigerant for Resale to Certified Refrigerant Technicians.

 

 

Edited by Starfighterpilot
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