Stupid question.....
When charging the system, should the can stay upright? Can it be turned upside down?
I know that that gas will exit the can when it is upright and liquid (theroretically) will exit when it is turned upside down.
What is the right way and the wrong way?

 

Someone told me the reasoning behind it, but "they say" you aren't supposed to charge with liquid from the low side, I think it has something to do with liquid refrigerant making it to the compressor and hydrolocking it or something. I honestly don't remember, it's been a while since I've charged something with cans. I do remember doing it both ways, with the can upright or upside down, and I never had any problems with it. If it doubt, leave the can right side up and let it do it's thing slowly.

 

Okay, just finished recharging it again. Here's the scoop:

Running it yesterday, the air coming out of the vents did not feel very cold at all.
This morning, charged it up with controls set on max a/c.
The cheap Wally World recharging kit gage showed on the low side of the filled mark (blue). When I finished, it was in the middle towards the high side of the filled mark. It sure didn't seem like it took very much out of the can, if it took any at all. Almost like it wasn't sucking any out. Yes, I shook the can and there was refrigerant in it before I started, and there is still some in the can after I finished. It's a small 13 oz can. The can got cold after I opened the fill valve when I began to charge it. Compressor is still cycling as opposed to the last time I charged it as the compressor stopped cycling and seem to run a long time before stopping and starting again. Maybe it's the ambient temp? But max a/c temp setting on the EATC is 60 deg. It wasn't 60 deg in the cab.

Anyway, I got my inside/outside thermometer from the house and stuck the probe in the vent outlet on the right side of the steering column.
the air was wavering between 58-61 deg. So I just sat there and let it run. I ran the idle speed up to 1500 rpm a few times and the temp dropped to 52-53 deg. Back to idling. 51-52 deg.
manually slowed the fan speed down a bit. Temps lowered...50.5...50.2...49.5...
lowest temp I got was 48.2 deg at a lower fan setting. hit auto button and temp raised to 51..53..54.....slowed fan down....temp went back down.

At 9:30 this morning it's 81 degress here and going up to around 92.

It will probably run colder as I'm driving it.....maybe.

Why does it seem like it didn't take any refrigerant out of the can?
Does it suck it out so slow that it's like pouring cold molasses?

Before I started to fill it, the gage indicated that the system was filled, although to the low side (yes, I know the gage is a POS, but it's better than no gage at all) Would that indicate that maybe I really don't have a leak, or the leak may be so slow that it takes a long time to show a low level?

Am I doing the correct thing here? Is it sucking out of the can? I have another new can that's 14 oz. If I take the fill valve/gage/hose setup off of the 13 oz can, it will spray refrigerant out because it's not empty yet.

I really don't know if there's anything else I can do at this point since I am no A/C expert.

Can I have your input? And Quintin, what do you think? How would you diagnose my system if you got it to work on at your place?

 

Okay, I'd try flipping the can upside down and letting liquid into the system now. If the compressor is still cycling at idle, it's still low.

If I were working on it, I'd recover all the refrigerant and see how much is really in there, but that ain't an option for you. With ambient temps like you described, the compressor shouldn't be cycling at idle.

As far as a leak is concerned, it's possible that given the age of your truck, the system might just be a little low without any leaks. Some refrigerant loss over the years isn't unusual.

 

Alright Quintin, I went out and did what you said. hooked it up and turned the can upside down. it stopped cycling right after I opened the valve and the fitting on the can got cold. It still didn't seem like it emptied the can, but I stopped when the gage started going up into the yellow area (past the blue "filled" area).
It's not cycling now, and it might get cooler when I drive it.
I just don't want to overfill it, and I don't trust that gage as much as I wish I could.
But it stopped cycling!
Do I dare add more? Maybe not.

 

Drive it and see what happens first.

 

Okay, I drove it. Just got back from Wally World.
The air coming out was cool, but not cold. Even though the air was blowing cool, I was still sweating a bit. The compressor isn't cycling, or it's cycling very little. It seems to just run.
It's better than what it was yesterday.
Maybe this is as cool as it's going to get?
I think the temps can get down to the low 40's at least. A few hours ago they were in the high 40's. Maybe wait a week and then possibly add more next weekend?
That damn mystery can is still not empty. I would have thought that I would have emptied it this morning.

 

Running to much will give you the same effect as not having enough. When installing refrigerant turn the a/c to max, which sounds like your doing. The best thing to do is have a shop remove all refrigerant and place the system under a vacuum and then refill.