My air conditioner had a problem a few years ago. While idling in the driveway on a really hot day the clutch on the compressor froze and nearly burned the belt off of the pulleys before I killed the AC. I continued to drive the vehicle for several months but without using the AC.

Fast forward 5 years (almost) and I just finished installing a new engine and putting a shift kit in the transmission.

Remembering the original AC problem I know that I need to get this fixed. I noticed while checking all the engine functions that the compressor clutch is not stuck any more (maybe all the oil leaking onto it helped with this).

As it stands now, the AC seems to cycle normally but it doesn't get cold and probably needs a charge at a minimum. Is it possible that the compressor clutch will work fine or is it a disaster waiting to happen? What else should I check in the AC system?

I am about to take a long road trip in this Bronco and need a little advice if someone has any.

I'm not against replacing the whole system or any single part of it. I am also not sure whether the AC uses R12 or R134. How can I tell?

Thanks.

 

I have checked the fittings and I'm pretty sure this is an R12 system. The fittings are both screw-on.

How difficult is it to upgrade this to R134 for someone who has no AC tools in their shop? Is it better to let someone else handle this upgrade? Does anyone know a reputable AC repair shop around Weatherford or Ft. Worth, TX?

Thanks.

 

I had the same problem with my 91 F150, well sort of. My dad owned the truck before me. He grenaded the compressor. It sounds to me that you have a drive bearing in the compressor ready to take a dump. Luckily for you, it sounds as if you haven't broken the compressor internally, which usually causes a plugged condenser (the reason mine didn't work right for about 3 years). Now, this is just my advice, and others might tell you otherwise, but if it were my truck, I would replace the compressor and clutch, the accumulator/drier, and the orifice tube. Since it's gonna be apart any way I would convert it over to 134a. Now the down side. If you don't have the proper tools, it will be impossible for you to do the work your self. Find a reputable shop, of which I have no info for ya, because I live in NE, and when they do the work make sure they flush the system properly before putting it back together. In order to do the install correctly, you would need a reclaimer, gauges, and a vacuum pump. I guess I am telling you this, because I would hate to see ya have it charged, and then be on that long road trip, and have the damn thing lock up and torch the belt.... Good luck, and let us know how it goes! By the way, this is merely my opinion....

 

Sparrky81 I appreciate the good advice.

I have had a chance over the last few days to do a bit of research and it all confirms what you are saying - if I don't already have the tools it is probably too much for me to take on and while I'm solving the compressor clutch bearing issue I probably need to go ahead and do the upgrade to R134a. I definitely don't want the belt to toast just as I get within a few miles of the middle of nowhere.

I've been calling around here in town to find someone to do all this and not having much luck getting it in and out in a reasonable time period. It seems with the 105+ degree days we're having that lots of people got their vehicles in line ahead of mine.

Just my luck that the one place that would get it in tomorrow wants to skip the R134a upgrade and just recharge with Freeze-12 which is compatible with the R12 that is currently in the system, at least I think there might still be some in there. I don't have any way to know for sure since I don't have the tools and when I turn the AC on it does blow slightly cooler than outside air temperature - but not much.

What good things do you have to say about Freeze-12? (If anything.)

I have also found out that R134a is on the way out since it too is an ozone-depleting greenhouse gas so I'm not totally convinced that the upgrade to R134a is the right path though it does turn out to be the only path offered anywhere so far. It may be better to keep it an R12 system until the next retro-fit gas is approved and I can do it according to what I have read as long as there are no leaks in the system.

What do you know about any of that?

It seems that the next refrigerant to be used in new cars was just approved a month or so ago and will be appearing in cars in the next few years. It's called HFO-1234yf. Here's a link for anyone interested:

Substitutes in Motor Vehicle Air Conditioners | Alternatives / SNAP | US EPA

Future Alternative Refrigerants (Brief explanation here)

The other thing that I had considered was finding a shop that uses FRIGC FR-12 since it can go right into a system that originally used R12 without any modification and is also compatible with R134a since it is a blend. It doesn't appear likely that I will find anyone around here to do that though since most independent shops are set up to handle one type of refrigerant, R134a, and anything else in your system is a no-go for them.

Lots of money though no matter what I do.

Thanks for the information. It's nice to have someone with some experience to confirm my own conclusion.

 

I don't have any experience with the Freeze 12, but have heard good things about it. The new refrigerants I am clueless about, as I don't do comfort cooling anymore as a living, and am now an ammonia refrigeration mechanic. So, I have no idea what is compatible, with what oil, and if it is a drop in or not. I wish I had more info for ya, but I don't.

I do know that 134a will be available much longer than R-12, which to my amazement is still available. The Freeze 12 seems like a good alternative, but I would still get rid of that old compressor, no matter what you decide to do for the refrigerant.

My p/u was converted to 134a before I got it from my Dad, so the choice was easy for me. I don't know alot about automotive a/c, but doing refrigeration for a living, I know how they work, and what has worked for me on my own p/u. All a/c works the same, there are just more accessories the fancier it gets. So, I try to help out when I can.

I hope that it all works out for you, 105 degree weather is no fun with no a/c.....I don't know how you guys put up with heat like that. Then again, you probably wonder how we make through the winters up here....

 

Thanks for everything Sparrky81. Lots of good information from you.

One funny thing about the heat down here - I didn't own a vehicle with AC until my wife bought this 92 Bronco new. I always rolled with the windows down and the stereo up and never missed it. Now, years later I'm softened up a bit and running with the windows down is a lot less appealing.

I know you have adapted similarly to the winters, which I wish we had more of down here. My brother is in Maine just south of the Canadian border and he's adapted well after only a few years up there.

Have fun and thanks for the info.

 

Freeze-12 is just R134a with some R142b blended in to make it compatible with the R12 OIL currently in the system. It works just like R134a. It cannot be mixed with existing R12, the R12 must be recovered first.
Considering that the newest R12 systems are 17+ years old and in need of rather heavy service, it's not an option that makes much sense.

HFO-1234yf is going to be cost prohibitive for quite some time even once it's released. I've seen estimates of $20-50/lb. There's also not going to be any aftermarket support for quite a while. Production is going to be low until it has been proven, and the OEMs will get the vast majority of that.

When reading the EPA list of "approved" alternates, keep one thing in mind. The EPA doesn't make any determination about how suitable an alternate is for any application. They are only concerned with environmental impact. CO2 is an "approved" alternate but it will not work in any current vehicle AC system.

 

Very true what you have said. It really looks like the only real option for the AC on this right now is to upgrade to R134a since it will be widely available for a long time even after the introduction of HF1234yf.

The cost of the upgrade is pretty steep though locally since I have to pay someone else to do it. $1500 seems to be a good ballpark estimate labor included. Right now that is just too much. The outfit that was suggesting Freeze-12 quoted $850 for the R12 recovery, compressor check in case bearing is bad, etc., accum/dryer, recharge w Freeze-12. Maybe I left out a few parts but that was his in and out price to make it run with Freeze-12.

This project just got shelved for a bit after I had a brake caliper freeze and trash a rotor this morning while I was on my way to get the AC service done. We're gonna get back on it after vacation and just rent a vehicle for the trip so that I can get all the right parts ordered and have the time to install them and do the things that I normally have to do anyway - like work.

I appreciate everyone's input and all the useful information.

 

If you can do general repair work on your truck, you can fix the AC system. The only tricky part would be access to compressed air for flushing
. Here's an option:
You do the cleaning, flushing and parts replacement then have a shop evacuate and charge the system.

 

After all the reading and accumulating all the bookmarks from others who have done the AC work, troubleshooting and upgrades I can definitely do the work if I get the parts together. Lots of smart people have put some very useful information together and they deserve major thanks for their efforts.

The stumbling blocks for me have been the ability to evacuate the R12 - no one that I've talked with has been willing to evacuate it unless they get to do the parts check, parts replacement steps.

The other stumbling block is the time constraint.

I got rid of the time constraint by (unintentionally) trashing the rotor so now we go back into my shop where I don't have to get to it until after vacation, a big relief for me.

The Autozone doesn't have a machine or they're not set up to evacuate R12 any more. I know I can get it charged anywhere but I think these shops smell a fat wallet when someone comes in needing some AC work. I might have to do more local calls to find someone who will evacuate the R12. I'm gonna keep that as part of the plan since I don't have to have this by tomorrow any more.

Thanks for all your help. Great forums and knowledgeable people really help a lot.