Opinions on air conditioning....

[Tigger]

I’ve owned my Saleen for almost 10 years now. Never did anything with the air conditioning other than flip it on when I bought the car to see if it worked. It didn’t. Car is all R12. It has not been messed with other than when it was in an accident by a previous owner many years ago. Last summer I hooked up my manifold gauge to the low side to find there was still a tiny bit of pressure still in the system. Since we have had temps in the 90’s recently and looks like we will for a while I put a vacuum on the system tonight. To my surprise it held. I still have some cans of r12 at my moms house. I was thinking about charging it and seeing what happens. Is there anything else I should check before I do that? How much Freon does the system take?

Thanks

[Ourobos]

Should say on the sticker in the engine compartment, usually around 30oz IIRC. If it's been sealed and remains sealed, pour it to it.

[Turbosvo86]

I would recommend you changing the "O" rings on your high and low connector fittings before you add the refrigerant. A very low cost of preventative maintenance vs. the high cost of R-12. Mine was rated 2 lbs. 10 oz.

[Tigger]

Thanks guys, the stickers are long gone. I will look into changing the "o" rings. I assume I can use the green R134 o-rings as replacements with no issues? The low pressure side fitting is on the compressor. I assume the high pressure fitting is on the metal line that is next to the distributor? My manifold high gauge hose will not thread onto that fitting. It is too big.

[erratic50]

The o rings that go are on the passenger side by the air box are the ones that go out. Order the spring connector clamps before you go through the trouble as they are a life saver.

usually need 2 1/4 lbs on an evacuated system.

2 1/2 if you do the ol displacement trick to force the air out of the system from the low side with the AC off and the high side schrader valve open until it comes out the other side.....

[emerygt350]

I use redtek r12a and it is awesome. Supposed to be compatible with r12 and works way better that 134.

[ashley roachclip]

Is that redtec a propane based coolant ?
If so that is not a path I would take .
R12 to 134A is easy to do and safe .
No need to purge the oil from the compressor .

[emerygt350]

Yep, course considering you are dumping gasoline into that engine I would be super worried about propane... hah.

[erratic50]

If you have gas lines inside the car then this would be similar

[KevinK]

Pumping the system down really did nothing but dump any existing Freon into the air. It’s a different story if you fix any existing leak then pump it down. Replacing just a couple of orings is just a shot gun fix. Replacing all the orings is simple and cheap. At least this shotgun method will have a better chance of success.

All ac systems are prone to small leaks and sometimes are undetectable. Since you found Pressure in the system, that was a good indicator you system was not in really bad shape. A thorough check for leaks might show no repairs are needed and just needed to add a bit of Freon.

Not everything about AC systems is overly complicated.

[Tigger]

Pumping the system down really did nothing but dump any existing Freon into the air. It’s a different story if you fix any existing leak then pump it down. Replacing just a couple of orings is just a shot gun fix. Replacing all the orings is simple and cheap. At least this shotgun method will have a better chance of success.

All ac systems are prone to small leaks and sometimes are undetectable. Since you found Pressure in the system, that was a good indicator you system was not in really bad shape. A thorough check for leaks might show no repairs are needed and just needed to add a bit of Freon.

Not everything about AC systems is overly complicated.

Kinda was thinking about doing them all but I’m also worried I’m going to induce a leak if I mess with it. Seems like my luck lately with things. Right now it seems to be sealed. I had the gauge on it for over two hours after pulled it down for 30 min. The needle stayed on 20 the whole time.

If I decide to change them all is it ok to use the green r134 o-rings.

[Tigger]

Order the spring connector clamps before you go through the trouble as they are a life saver.

Which ones are you referring too?

[mudgepondexpress]

You are fine using the green 134 o-rings. Buy a kit at Napa, AutoZone, etc, it's cheap and has multiple o-rings and the springs.

[2nd chance cobra]

Anything that is not actually r12 I would be very leery of. I watched a video back in college of a single can of replacement r12 leaked into a camaro, it was lit off and blew the t tops off windshield out and burned everything inside beyond recognition. But hey is was just a camaro. I'm sure it would be completely different in a fox. I've done lots of 134 conversions. Fix what's broke, change the drier, add the new fittings add compatible oil and charge it up. Always had good luck with it

[emerygt350]

Good thing I have a convertible then...

[Tigger]

You are fine using the green 134 o-rings. Buy a kit at Napa, AutoZone, etc, it's cheap and has multiple o-rings and the springs.

Thanks, I have a kit already which is why I was asking

[homer302]

....A very low cost of preventative maintenance vs. the high cost of R-12. Mine was rated 2 lbs. 10 oz.

Can't believe this myth still persists to this day after over 20 years. R12 is the cheapest freon anyone could ever purchase. Is it more than it was in 1985? Yeah, I guess that certainly is true. How much was a gallon of 1985 gas (or a new 1985 Mustang) and how much are they today? Everything is more expensive if you look at it that way. I don't know where the idea that it's expensive ever came from. There is ZERO demand for it. It's everywhere. No demand = cheap to buy.

To the OP, the sticker is only a guide. Every system is likely to be different and over the years parts have been replaced etc. that might change how much is required. You can tell by the low side Pressure when it is full. You want it around 25-30PSI and that somewhat depends on the ambient temperature and humidity but that will get you very near. As you add, you will see the low side drop and drop and then it pretty much just quits dropping. You may as well quit trying to fill at that point. It's as low as it's going to get. That tells you that your particular system is full. Of course shove a probe style (think fridge thermometer) into the center vent with MAX AC on HIGH as well

[ashley roachclip]

R-12 was made extinct because of enviromentalists.
2 pounds of this gold here will cost you 200 bucks plus labor to fill system .
And you will need to have a license to handle it .

I challenge you to find it at your parts store .

On the other hand , 134a is at every parts store , you can charge your own system without a license , and it will cost you around 50.00 .
Walmart carries a 2 lb can with the charge hose , for 49.99.

No 134 does not cool as well as the r12 did , but it is in all new cars and trucks.

[homer302]

My assumption was that the person looking for R12 would be a tad more resourceful than driving to Advance Auto Parts to get it and then only having it installed by a "licensed" mechanic that is certified to handle it. It's everywhere and it is dirt cheap.

[ashley roachclip]

Not here on the left coast .
On occasion I have found a few small cans , not enough to fill a system .
I did find a 5 lb can on craigslist the other day for 375.00
Not all of our members are as mechanically inclined as others , but they are trying to learn .
For that I give them credit .

[Saturn V]

OK, I'm like homer sometimes and so I didn't read each and every reply above. But I think there were a couple of comments above about going ahead and replacing all O-rings. If you have a good vacuum pump, you might as well just go ahead and replace all seals. Just get a complete seal kit ... includes all of the O-rings and new Schrader valves at test ports and low pressure switch. I think I got mine on Amazon ... easy to find. Just don't leave the system open to atmosphere very long (minutes - ~hour is OK) or the drier will absorb moisture and this will negatively affect system performance and life. I had a mechanic buddy help me with the seals on mine this spring, since he was already familiar with the job and I wasn't sure what surprises I'd find. When you break open the lines to replace the O-rings, pay attention to the condition of the oil. If it looks clear (or slightly yellow and clear ... see pic below) and there are no signs of corrosion inside the lines, you will probably be OK. The sticker above my radiator says 2 lbs, 10 oz. of refrigerant. That's 42 oz. I have 12 oz. cans of R-12, but remember that you have to subtract the tare weight (the weight of the empty can). My empty cans weighed about 1.5 oz, so 4 cans delivered right at 42 oz. of R-12 (4 x 10.5 = 42). Pressures were good with this charge and I've seen vent temps in the low 40s.



I can find R-12 in the Houston area any week on Craigslist for $20-30/can. Sure, it may be more expensive than R-134a and not as easy to buy (have to meet with a Craigslist person versus Autozombie), but you can still get it. I can find no evidence that R-12 is illegal to buy or use in CA, or any other state. So I don't know why it should be any more expensive out there. With my seal tuneup, I don't expect to need to recharge my R-12 anytime soon, maybe never. So I was glad to spend ~$100 on R-12 and not worry about the R-134A conversion expense and hassle. And if I do need R-12 in the future, and somehow lose the spare cans that I bought, I'm sure that I will find it for sale. And the reason R-134a doesn't work as well in our cars is because it needs a larger condenser. So putting in R-134a in a stock Fox will result in poor performance of the refrigeration loop. That's why you need to replace the condenser with a larger unit as part of an R-134a retrofit.

If you want to be strictly legal, get your EPA 609 license for $20 at the link below. That will allow you to legally purchase and install R-12. It's an open book test and pretty easy to pass with no pre-study.

https://www.epatest.com/609/

[Mgino757]

For what it's worth, my 85 was converted to R134A a long time ago. I have no complaints on how cold it gets. It'll fog up the outside of the windows with how cold it'll get the interior.

[MOOSH]

You just need to buy an adapter to fit the gauge to the fitting on the line. I'm at work or i'd send you a pic of the one I have.

For what its worth, I recently had to replace the high pressure hose going from my compressor to the condenser and the o-rings were fused to the hose and condenser fitting. It was never going to leak there. ever.

Lastly, I converted mine to 134a a couple years ago, I have had no issue with its ability to cool.

[SECESH]

I'm almost always sorry when I disassemble something that is/was working. Too often run into the can of worms that might have been avoided. Manuals will usually suggest adding some refrigerant and then checking for leaks. Soapy water works for places that can be seen. An electronic detector would probably be necessary for the evaporator.
Sometimes a seal will hold vacuum but not pressure, kinda like the bandage for a sucking chest wound.

[Ourobos]

If you're worried about leaks, the biggest place to look and R&R is the high and low side valves.. Replace those for like $10