A/C Conversion R12 to R134a

[apstguy]

I finally am picking up parts for my conversion today. Got the regrigerant and a pressure gauge form Target (of all places!). I went to the parts places to get the o-rings, orifice tube, accumulator, and high pressure switch. The automatons at the parts place said the don't even carry o-rings for these anymore. They still can get the accumulator. The orifice tube and high pressure switch has to be an r134a, but since it is not original to the truck I might as well have been speaking greek. Can anyone help me locate these parts? I lost the link to the site I was going to use for the parts. Thanks guys! I want this done before it gets >95 degrees.

[mhorning]

I know I'll get blasted for this. But I bought the conversion end to go from R12 to R134 screwed it on and filled it up. That was a year ago and it works fine. Did the same with a VW I had and it continued to work for 4 years after the install. Still working as far as I know- sold the car. I had a friend who was an AC repairman who verified that I could do this. Said that the kit wasn't really necessary. I'd be interested to hear others on this. But it might save you a few bucks.

[ocbaud]

tyler, do you mind getting a complete parts list of everything you need to do this when you are done. i took the r12 compressor out of my truck and want to replace every single a/c component with all new parts and run r134a in it

[apstguy]

I know - I already have the kit but with these trucks, the compressors only last a few years after the retrofit. I want to make sure I do it "the right way the first time". I really don't want to half ass it - besides, it isn't just blowing hot air, the compressor ceazed up and probably threw crap into the lines and the whole system. I'm only going to do this once.

[apstguy]

No problem. I'm going to start to chronicle all the upgrades I do like this to make it easier for others to find and do.

[mike reeh]

maybe it would be money better spent to go with a stock setup and have it charged with R12. It will be a little more expensive but better IMO in the long run. Im going to do mine w/ R12 pretty soon... Dont forget to have the entire system evacuated before charging it

mike

[apstguy]

R12 is too expensive and it is very hard to get ahold of in CA. I think R134a is better in the long run. These compressors can't take much. As soon as a rebuilt goes, you in the same situation. I'm buying flush and am going to evacuate it w/ a full setup my cousin's uncle has. He has all the equiptment for this as he runs a farm and converts all the time.

[TIMSPEED]

Tyler, to get the parts you need, I would go over to this guy who does A/C. He's on McHenry, right DIRECTLY behind that furniture place, just past Pelendale/Claratina. He is a very honest guy, and will help you out as much as he can. (He carries all kinds of crazy parts.)
He charged my R12-equipped saturn for $150. ($50 a pound)

[mike reeh]

Originally posted by apstguy
R12 is too expensive and it is very hard to get ahold of in CA. I think R134a is better in the long run. These compressors can't take much. As soon as a rebuilt goes, you in the same situation. I'm buying flush and am going to evacuate it w/ a full setup my cousin's uncle has. He has all the equiptment for this as he runs a farm and converts all the time.

I made it a point to say it would be more expensive, but getting ahold of r12 is a non issue. anybody that can evacuate the system can get your freon. What do you mean the compressors cant take much? My original compressor worked well for 25 years. It would still be working if I didnt remove it.

As soon as a rebuilt goes, you're in the same situation? That why I insist on quality parts from the get-go. When and/or If the compressor went bad, you have your AC guy reclaim your still good R12 for later installation after you fix the compressor.. The fact is, to do it right you NEED specialized equipment, which for most people means you have to pay somebody to do it. If you are looking for the cheeseball way out, just fix any leaking hoses and charge the system yourself with some 134a. It will work. many people including myself have done it with great success.

mike

[apstguy]

My truck never leaked freon at all. The compressor just blew up. Smoke, color and light. Did I mention it is now yellow and green? A brand new compressor is $700. Rebuilt is $120. Hmm..... I'm not Bill Gates. The matter of this is that I want to convert to R134a ANYWAYS. My compressor went 18 years. The rebuilds are much less durable (partly because of improper installation like not flushing the system). Anyone who has ever had one of these things go knows what I mean. They are radial compressor which were only used on 80's-90's SMOG motors. Axial compressors are much more durable and slightly more efficient compressor. If I really wanted to do this ultra right, I would get a serpentine pully system off a wrecked 96-98 truck or SUV, get the compressor, and get custom flexable stainless steel braided hoses.

Where is Mike when I need him??? Cheap is not best.

[Bowed]

www.aircondition.com

The above site has a forum on auto air with some very good input . On the subject of R12 , it is selling in my area for $100.00 a pound and will continue to rise . I have been told there is a low priced replacement that has come out that is compatable with R12 and can be added to an R12 system but I have not been able to find the name of it yet .

[Grim Reaper]

Originally posted by mike reeh
maybe it would be money better spent to go with a stock setup and have it charged with R12. It will be a little more expensive but better IMO in the long run. Im going to do mine w/ R12 pretty soon... Dont forget to have the entire system evacuated before charging it

mike

A "LITTLE"? Have you priced R12 in the last 5 years. It's $40 a can now and you have to have a license to buy it. Something like my Dual air Sub talke 7.5 lb's of the stuff. That's about $320 in freon.

Here is the big problem with converting. R134 has a higher head pressure. It takes more power to drive it. Then it's less effective. New cars have a larger conensor and evaperator to make up for it. It would probably be ok in a truck but it sucks in my Burb even with the dual air.

Also the molecules in 134 are smaller then R12. A hose that was holding R12 just fine nay not hold 134.

Tonight I am putting in a couple cans to get it going for the trip to FL thiss weekend.

[Grim Reaper]

Originally posted by Bowed
www.airconditioning.com

The above site has a forum on auto air with some very good input . On the subject of R12 , it is selling in my area for $100.00 a pound and will continue to rise . I have been told there is a low priced replacement that has come out that is compatable with R12 and can be added to an R12 system but I have not been able to find the name of it yet .

It's called Freeze 12 or something.....It's basicly popane. Propane makes a better refrigerent then 134. It just happens to make a lot louder noise if it excapes near an ignition source.

[Slonaker]

A friend of mine who used to work for Vintage Air suggested buying street rod brackets for a more efficient late model compressor. They are less expensive, readily available new, and use a lot less horsepower. He has gone this route on his daily driven 327 powered S10, and is very happy with it. You would have to get hoses custom made, though, but he says that they are not expensive.

When I have a little bit of money, I would like to go with this option.

My A/C is out right now, and it is starting to get warm outside. It is supposed to hit 81 degrees today. I have a spare cheap rebuilt compressor sitting on my shelf right now, so it will go on there this time if I need it.

BTW, I priced a new (not rebuilt) stock radial compressor locally about a year ago. I think it was about $300. Not cheap, but probably a better option in the long run that the junk rebuilds (like the one on my parts shelf...) that everyone carries for $100.

Slonaker

EDIT:

I think that Bowed might have meant to link to www.aircondition.com for their forum. One of their sponsors, local to me, lists a new compressor with clutch for $240. That sounds pretty cheap.

http://www.caawparts.com/

Regarding o-rings, I would suggest that you do like I did. I went to an automotive A/C supply place where they knew their stuff and asked for one pack of each o-ring size that my truck uses. They said it only used around 4 sizes, and a package of each was less than $5 total. That will, hopefully, keep me from running back and forth between the house and auto parts store.

[arveetek]

R12 is good, but it's expensive, and nearly impossible to locate. It hasn't been manufactured in the US since 1995. That was 9 years ago. There has been a lot of R12 sold that is not pure 12, but a mixture of various refrigerants being passed off as R12. Unluess you have several cans of the R12 still sitting on the garage shelf, or bought a big 30 lb. container of it before it went off the market, then I wouldn't trust anyone selling R12. It's just too hard risky.

That being said, I'll tell you my experiences.

A few years ago I started running propane in my a/c. Cooled great! Better than any vehicle I ever drove. I rigged up a way to inject propane out of a 30 lb bottle directly into my system. I don't recommend you try this. It is very flammable! I finally decided it wasn't safe to be doing this, and changed over to 134a last summer.

I needed a new compressor anyway, so I replaced the compressor, lines, accumulator, orifice tube, o-rings, and removed the evaporator and cleaned it out. I think removing the evaporator was probably one of the best things I did to help the cooling effeciency. After running around in a pickup truck for 20 years, it was quite dirty. It wasn't very easy to do, had to remove the black housing on the firewall and all, but the results were fantastic.

I charged it up with 134a, and it works great. Cools better than the original 12 ever did.

The pressure switch is adjustble, no need to replace it. I just used the stock style orifice tube.

Casey

[apstguy]

With reguard to the lines, after 18 years of the oil running around in the system, it coats the hoses well enoguh to where they don't leak refrigerant. I'm not going to bother with new lines at this time as they work fine and havn't ever leaked.

[loblazer]

Hi guys:

Just thought I would throw out the name Duracool. I see this in a lot of hot rod books and sites. Replaces R12, is cheaper, apparently is colder than R134.

Doug

[mike reeh]

Originally posted by Grim Reaper


A "LITTLE"? Have you priced R12 in the last 5 years. It's $40 a can now and you have to have a license to buy it. Something like my Dual air Sub talke 7.5 lb's of the stuff. That's about $320 in freon.

Yes Ive priced it in the last 5 years and also bought quite a bit for myself and other people. Ive also never been impressed by any 134a system that Ive ever used, and especially not any retrofitted system. (im including late model 134a designed systems too like in my toyota, in that generalization)

as for getting bogus "r12", you can still get dupont freon at lots of parts houses in california.

I really like the propane idea. I would definately put money into a propane retrofit before I did a 134a retrofit. albeit dangerous! With new hoses and a good compressor and stuff, Id feel pretty safe about it. Cant be much worse than having 40 gallons of gasoline under you at all times. When I really do my AC system up in the '77, which wont be for a while because I need a new cab, Im going to replace anything and everything that needs to be replaced, and run an electric fan on the condenser. also going to go thru all the ventilation ducts & valving system in the dash.. There is a LOT of potential in these old trucks, but after many many years of service it needs a little attention. When these trucks were new they would freeze you out of there on a hot day. There is no reason they cant be that good or better, now

mike

[Bowed]

QUOTE posted by Sloanaker "I think that Bowed might have meant to link to www.aircondition.com for their forum "

You are right and thanks for the heads up . I corrected my original post .

[apstguy]

I went to the site and had a look around. Good info.

When I went to the parts store, they had 2 orifice tubes listed. The original replacment and something called a VOV. By looking at the site, it repalces the original orifice tube and puts a variable orifice valve in its place. I read up on it and am going to get one. Price difference it $3 for original orifice tube or $26 for VOV. I'm going to bite the bullet and try it.

[76HighSierra]

I did the R-134a retrofit about a year ago. I completely evacuated my system, installed the adapter-style high and low pressure fittings and charged the system. Here in New Mexico, the A/C gets used a lot....even some days in the winter. I never had a problem with my stock 28 year old compressor, or any other parts of the system. It all seems to handle the higher pressures quite well, but it's not worth a sh*t as a refrigerant, as compared to R-12. Doesn't cool at all well, comparably. As expensive as it is, when I rebuild my A/C system, I'm going to have it charged with R-12. Either that, or completely modernize the entire system to run R-134a. All I know, is that my truck blew ice cold with R-12 and it's only mediocre now running the R-134a. I should have left well enough alone.

[jimfulco]

The A/C places I've talked to have recommended using a higher-efficiency condenser with 134 if you're retrofitting.

[Grim Reaper]

Originally posted by apstguy
I went to the site and had a look around. Good info.

When I went to the parts store, they had 2 orifice tubes listed. The original replacment and something called a VOV. By looking at the site, it repalces the original orifice tube and puts a variable orifice valve in its place. I read up on it and am going to get one. Price difference it $3 for original orifice tube or $26 for VOV. I'm going to bite the bullet and try it.

Give us a part number. I think that may solve a issue I am having.

Because Mine is a dual air it has about 3 times the Freon as just a dash. Whe we hit these temps up in the high 80's I satart to have problems where the compressor will create so much pressure and the outside heat has caused the freon to expand. This will momentairily lock up the conpressor and slip the belt. I have managed to get it to happen a couple times while it was parked. if I kill the engine you can hear the presure bleeding off through the orifice tube.

The 134 cools just fine at 70mph turnign 2800 rpm on the engine. It the stuck in traffic where it start to suck! I'm going to re wire the factory electric fan (454 HD cooling FI deal) and see how it does. If that just stays on all the time instead of wait till the engine gets hot it may help.

2 cans of 134 went in last night. See how it does.