For Those Who Have Serviced Their A/C- High Side Port Question

[el ess A]

Ok....cranked up the 2010 SS the other day and pulled it out of the garage and took it for a drive uptown as it hadn't been used in a minute. It is pushing almost 14K miles now. Warm, but not hot morning, around 70 deg. F when I pulled it out of the garage. A/C has never been touched except for a belt changout a few years back as a precautionary move.

I noticed the A/C clutch cycling on and off about 15 second intervals as I was waiting for a Sirius/XM radio reload (as it had lost connection to the mothership apparently). As a precaution, I run the A/C with the blend door two clicks up from max cold. I didn't give it much thought as the air blowing out of the vents was cool, but it wasn't hot outside at the time anyway. I did not use any thermometers to check, though.

The A/C was blowing cool sitting there. After the radio got its signal back, I took it for a drive and the A/C seemed to work just fine. When I got home I just pulled it into the garage and forgot to check if the clutch was still cycling every 15 seconds or so.

I opened the hood and checked the high port check ball, and there didn't seem to be any oil or goo or anything. No visual signs of leaks anywhere under the hood. Everything is clean and dry. I checked the low port schrader valve too, but again, no obvious signs of trouble. I didn't do a soap bubble test on them, but I plan to. There's no dirt buildup on the condenser, as it lives in the garage a lot. Everything is clean and dry under the hood.

But, since these stupid high side balls eventually leak, I was wondering a couple of things:

1. Should I just go ahead and buy the Dorman schrader valve high side port replacement as an upgrade if I find the high side port to be leaking? (Dorman 800-955). Interestingly the 2012 Ford Focus has a schrader port on both sides from the factory and no leaks on it so far.

2. Simply hook up the A/C gauges and do a pressure check on them? If slightly low just top off the 134a and keep an eye on it? (most likely)

3. Obviously, it has a super-slow leak if this is the case upon leak check results. Again, I'll do some soap bubble testing on the fittings to determine how bad, if at all.

The nice thing is that, according to the 2010 service manual, GM was kind enough to charge the system with flourescent dye from the factory so it should show yellow/green under a blacklight. But now I just need to find my little blacklight flashlight.

4. Thinking about it, it's possible there may not be a leak, but to be sure, I need to do better troubleshooting. The garage was cool and so was the outside air when it happened. Generally cooler than normal, so increased cycling MAY be normal on first start with lower outside temps. I mean, it did seem to work fine on the drive.

Not afraid to do the work of recovering/evacuating and recharging if I have to. I mean, what does this thing take as far as a charge anyway, 21 ounces or so? (0.6 kg/1.32 lbs).

[el ess A]

Well, beautiful. I checked the Focus and both 5th gens for leaks and all the low and high side ports have a slight leak. I kinda expected that.

The gauge readings show the Focus to have just the right charge. Came up on 36 low side and 156 high side on a 73 degree ambient. No cycling, no issues it seems.

The 2010--- different story. I suspected a low refrigerant charge, so I just hooked up the low side and checked it. About 45 psi static. Hmmm. Still 73 degrees.

Cranked up the car, immediately the compressor was cycling between low 30 something and 42. As it ran, it got a TAD better, but not much. Cycling was 28 to 44 after about 1 minute or so. Done.

Considering it has had ZERO maintenance except for the cabin filter, 16 years isn't much of a leak. With the caps on, there's no detection of leakage by the electronic sniffer, and inspected the entire system again with it and nothing. Other than the port innards, I saw nothing with the blacklight either. Not even going to bother with a soap test. My conclusion is a 16 year leak cycle which doesn't really make me concerned at this point. It's still blowing 44 to 46 at the vents 2 clicks off of cold. Weird. TXV is probably saving it at this point.

Sure, I could change the high port and change the schrader in the low port, but they're not usually able to do perfect sealing anyway. If you think otherwise, you'd never have to add air to your tires.

I got to run to town and get some refrigerant, so I'll do that tomorrow and update as I get it done. Still need to check the ZL1, too.

[gtstorey]

Sitting is the worst thing for the compressor seals.

[el ess A]

Originally Posted by gtstorey

Sitting is the worst thing for the compressor seals.

While I agree just sitting isn't great, there's seemingly no issues with the compressor as far as leaks, even at 13,454 miles.

After measuring the 12 oz. net weight can afterwards (3.5 oz tare), the system was about 8 oz. of refrigerant too LOW!!! Which, if you look at it overall over a 16 year period (today is the car's 16th birthday, of all things), that's only 1/2 ounce lost per year. Granted, ideally it should be zero, but we can't all get what we want. But in a 21 oz system....that's a lot as far as volume.

80 degree day. Slow but sure as I added a little 134a at a time, the short cyling got longer and longer. Soon it was no longer. About 40-43 on the suction side and about 205 plus or minus on the discharge side. Pushed down outlet temps by about 3 to 4 degrees- final cabin reading was near 40 at the center vents varying a bit between 39 and 40 every so slightly.

STILL getting a teeny bit of seepage out the check ball and schrader valve per the sniffer. Black light shows nothing out of the ordinary, exception where a bit of oil that got out of the connection points, to be expected.

If I do take it down to change out the check ball to a schrader, I'll do the dessicant bag then.

I'm calling it good. Topped off the rad overflow tank and the washer fluid. Took it down the road and it's nice and super-frosty again.