R-12

[xplodezeus]

My AC slowly went out during the last 3 years. It just starting cooling less efficiently until this year no more cooling. I tried to get my hand on some r-12 but appears to be banned here in the U.S.

I guess the next option is the conversion to r-134a?
I read the write up on the main website But I was still unclear on how to complete the switch

I need a detailed parts list, the price for each part, and lots of photos.

I hope someone can help

 

[krugford]

The first thing you're going to want to decide is whether or not you really want to do it yourself. You're going to need some special tools. You'll need a way to pull a vacuum on the system to evacuate air and moisture, you'll need a set of pressure gauges to check high and low side pressures while you adding refrigerant, and you'll need a way to meter in the correct amount of refrigerant into the system. You can go by pressures, but the better way is to go by weight.

As for parts, since your system is now open to the atmosphere, you'll need a new receiver/drier. You'll also need a new orifice tube, and you'll need to find the leak that caused the problem in the first place.

If you don't want to go out and borrow/buy a vacuum pump and gauge set, you might as well take it to a shop and have them do it all because taking it to them just to evacuate the system and then doing the rest yourself probably won't save you much money, and if you didn't fix the leak, you'll be doing it all over again.

And don't use anything that says it'll fix leaks! The ONLY way to fix a leak is to replace the faulty part. (o-ring, line, etc). Stop leak will stop more than just leaks.

-krug

 

[exbass94]

Are you sure you have R12? My 1994 Explorer originally came with R134a, so I logically assumed that Rangers switched that year too. In fact, I was under the impression that every vehicle switched because R12 production was banned in 1994. But I could be wrong.

 

[Loanranger]

I'm pretty sure a 94 should have 134a already. If in fact you do have r12 still, and you are positive that you're system doesn't leak, call around to some collision shops, some still service R12 systems. It is still possible to get R-12, though it is around $300 for a 30lb bottle. If you do find a collision shop that has a dual (r12 and 134a) machine, they will usually recharge your system for around $75 bucks. The shop I used to work in had the dual machine, and used to drain the totals that had r12. So it IS possible to recharge. If you can't find anyone to do it for you, then it would be best to do the conversion.

 

[RobbieD]

1994 was apparently a mixed year. My '94 Ranger 2.3L has factory R134a, identified as such by the evaporator housing sticker and tags on the lines. BUT, it also had a small "Caution R-12 destroys the ozone blah blah" decal on the driver's glass. Earlier this week I looked at our 1994 Mazda B4000 company truck at work after it came back from getting its AC system fixed. It is plainly marked as an R-12 unit on the evaporator housing, and it still has the "Caution R-12" decal on the driver glass. So, two 1994s, one R-12 and one is R134a.

It's been two years since I converted my 1990 B2, so I'm working from memory here. When an R-12 system is converted over to R134a, EVERY o-ring in the system must be changed; old black ones to the green ones. I would have to look it up, but I believe that the reason is that the original o-rings are not compatible with the oils that have to be used with 134a. You also have to flush out all of the old mineral-based refrigerent oil. There's two refrigerant oil options for use with R134a; I remember that one is PAG oil, which I used as traces of mineral oil wouldn't adversely affect it. The other oil could not be exposed to mineral oil, or some kind of awful, terrible thing would have happened (reaction creating sludge, maybe, I think).
Edit- Ester is the correct oil which I used, not PAG.

On my B2 conversion I started with a new compressor, accumulator/drier and orfice tube. All of the other components came out of truck, were cleaned and flushed with the special gun and chemical (about 30 bucks, I think), and then everything was installed with all new (green) o-rings. In the Ford shop manual, I believe it was, I found instructions, that when replacing R-12 with R134a, to use 10% less than the R-12 charge weight. Always charge by weight, the exact weight specified, and add the exact amount of oil, as specified.

The conversion is still working perfectly, blowing cold air in the mid- upper 30s degree range. When I converted the AC I also did the Explorer radiator upgrade. It was well worth the expense and effort, but you can't do a conversion halfway and expect it to work right or last.

 

[MAKG]

That's backwards. PAG reacts with mineral oil. Ester doesn't.

 

[RobbieD]

Thanks, MAKG. Not surprised that I got 'em backwards; I should have been more careful. Trying to bang out a post when I should have been sleeping.

 

[xplodezeus]

thx for the replies guys some good info.

I'm not 100% sure its r-12
How would I be able to find out for sure?

 

[baddis]

look at the fittings if they have threads it is r12 if they are quick connect it's 134

 

[xplodezeus]

All right ... I know its been a while since I was last here but this is an update.

I found out my truck is 134a
I Therefore went and got me a charging kit.
The kit told me my pressure in side was good.

I noticed when I turn my AC on full the compressor won't stay engaged. Just clicks off right away. Does that mean my compressor is bad?

 

[skippy]

All right ... I know its been a while since I was last here but this is an update.

I found out my truck is 134a
I Therefore went and got me a charging kit.
The kit told me my pressure in side was good.

I noticed when I turn my AC on full the compressor won't stay engaged. Just clicks off right away. Does that mean my compressor is bad?

no,sounds like it's still low on refrigerant and going off on low pressure switch.however it's hard to diagnose without actually seeing your system in person.

 

[MAKG]

Another possibility is a blockage. One I'd tend to favor if the static pressure is good.

If there is a blockage, you have to fix what caused it.

You also have to FIND your LEAK.

If you're going to do this half-assed, it's just not going to work for very long.

 

[thegoat4]

All right ... I know its been a while since I was last here but this is an update.

I found out my truck is 134a
I Therefore went and got me a charging kit.
The kit told me my pressure in side was good.

I noticed when I turn my AC on full the compressor won't stay engaged. Just clicks off right away. Does that mean my compressor is bad?

Is that one of those kits that comes with just a low-side gauge? That really isn't enough to tell what's going on in your system. You can kinda work with it, but there's still a lot of guessing.

If that kit had "sealant" in it you've screwed yourself. If you do decide to take it in to a shop and have it done tell them up-front about the kit. Sealant plugs up expensive AC machines and some shops will bill it back to you, which can be a couple thousand.

Besides that, that sealant crap just clogs systems up.

Don't forget to look at the rest of the system aside from plumbing. A bunch of dirt clogging your evaporator core will stop the AC from cooling and lead to fairly rapid cycling. Same goes for the condenser core. A failed or faulty switch can cause the same. A weak auto-resetting circuit breaker to the AC compressor, etc.

When your compressor kicks off "right away" how fast is that? Less than a second, five seconds, what? Does it get better or worse after running a while? Will it stay on longer when your AC is not on "full"? And what do you mean by "full"? Just set on Max AC, or the fans on high, or something else?