Somewhere I lost the information on the upgraded AC systems in our truck, what they used to run and what they changed it too.

I though I recalled that they had to replace something in the system to do the upgrade? Which is silly name for it anyways, its just a coolant change.
Anyways.

Was that during our years of trucks?

If so, how can I tell if I have the old or the new system, so I can replace the parts before I take it to get it filled again. I don't have access to the tools to do it myself anymore, so I cannot just put in the old coolant.

 

subscribing

 

Do you mean the R-12 to R-134a conversion?

 

A quote off of another website (near the bottom of the page): Alternative Refrigerants for R-12

Switching an older R-12 system to R-134a does not require a lot of modifications in most instances. Changing the accumulator or receiver-dryer, removing the old compressor oil and replacing the high pressure switch is generally all that is needed. For more information, consider purchasing the R134A RETROFIT GUIDE on this website.



If you do the conversion, you wont get as much kick out of the a/c as you would with the R-12. Before I got rid of my 88, I recharged it with a product called Freeze 12. It seemed to work really well and the a/c was ice cold, plus it was a lot cheaper then R12 which is getting harder to find and more expensive.

 

All of ours came with R134A in them. Nothing to convert. The change was done between 92 and 93 for Ford depending on where they were built. I think 91 was the last year all Ford trucks had R-12 in them.

Be careful with freeze12. I never cared for that stuff. It's easier just converting an older one to r134a the right way.

You can always tell the difference between a 134 and a r12 system easily because R134A service valves are quick connect design and R12 is thread on design.

 

Having went to school for HVAC stuff, I kinda dont like the idea of some of the "quick fixes" when I know how to charge systems properly.

But thanks for that info Dan. That's what I wanted to know. As well as the replacement parts.

 

Those kits aren't much good except for the fittings and can of oil you need. I like to put in a van orifice tube for a 2000 model full size or so. That pretty much makes it just as cold as a r12 system without freezing up your evaporator. You have to change the dryer too. That's just not an option when you know how air conditioners work is it? I see too many people doing it without a vacuum pump too. It will never be right then.
Talyn, if you ever need help or tools or whatever for converting a car then you know how to reach me. I've done one or two.

 

I've done plenty of AC systems in the college, but we didn't do Car AC systems.

But yes, the filter is important also.

I never did quite understand how you could have oil in a system and not have the filterdryer not soak it all up.

Never had any to cut up in class. =(

The best thing about AC systems is that they are all the same thing.

And you are 100% correct about pulling a vacuum and testing for leaks.

If you don't pull a vacuum, your damaging the system and it will never work properly. Air and moisture are the worse problems for an HVAC system.

Pulling a vacuum on the system eliminates all moisture and junk in the system.
It cleans out contaminates and dirt.
There are other gasses that you can use to clean out the system as well for an older system, but you still pull a vacuum again.
The vacuum is what allows you to add the coolant.

ahh, whatever nobody cares.

 

When it comes to good working ac, I care!

 

Talyn, Pulling a Pulling a vacuum doesn't really remove dirt unless it's stuck in the small amount of oil that comes out. It's just air and non-condensable gasses is all. When I worked on big units , like 8 and 12 cylinder 100 ton yorks, we'd pressure test with nitrogen all the time to check for leaks. Then by Navy standards we'd pull and hold a vac for 24 hours and couldn't have more than a 2 in/mer drop in that 24 hours. That was the easy standards. Submarine systems just sucked!! Cars are a lot different. Law may have changed but it used to be hold vac for 30 minutes with no more than 2 drop. I think it's 15 minimum now but whatever....If it's more of a drop then you still have air in it or a leak. I like to leave my pump running overnight though when I've had the system open then hold for at least an hour. Never hurts to do more. It doesn't pay for a mechanic to do that on flat rate though. I'd do everyone like that if it did.

I've never had a newer dryer open either but I've done a lot of the old GM serviceable dryers. THose you open up and it's just a plain old desiccant bag in there with a txv. It comes in a kit and you just rebuild them. I miss those. The compressors were just as easy to rebuild back then. It was a 15 dollar kit!!! I still have some remy delco kits in my shop for compressors and dryers.
I'm putting a txv on the system I built for the house a couple years ago probably next week. It's a 5 ton and I went cheap with a fixed orifice. It sucks with the temp swings we get here! Why don't you come help!!!!

 

yeah yeah yeah. went though all that in class.
Just no reason to spent 30 mins typing up ALL the details of what things doo.
Specially when most of the information goes over peoples heads.
I employed the KISS method.

The dryer I did see in class was like what you described, as is how the teacher described it. Probably a bit more fancy now days, but same concept.

To bad lots of the AC units for fridges and stuff are sealed compressors.
I'm not quite as old as you are. :P
So I didn't get to see some of the older stuff.
We did a lot with big walk in freezers and Air conditioning units, furnaces, geothermal.

It was neat for me to learn that its all the same thing. Same system, same concept, same principles in every system.
Just the scale and application of the parts used, and occasionally an extra part.

 

Man I'm not old. I was on 3 ships built in the 40's though. One built in the 30's and 2 built in the 70's. I learned a lot. I've worked on a lot of antique cars too.

 

So, your an antique?