I would suggest actually replacing the core in the valve, rather than trying to make a cap to hold the refrigerant in. Ever changed the core on a tire? You can pull the old one out, and put the new one in quick enough that you won’t lose all the refrigerant, thereby reducing/eliminating your need to vacuum the system. As long as you have everything ready, and the system isn’t under any running pressure…
Chase
ok4450:
I don't know if "I" can reclaim it ... I'm guessing I cannot. But what I was thinking is if I could "cap" it so that I could drive it somewhere to be reclaimed ... I was thinking last night that if I had a gauge set (or even just the hose from one) that had the shutoff valve on the end - that would work for me! And no, I don't think there is any problem with the (MasterCool) gauge set. They seem to fit just fine and there are no leaks as long as they are pressed down and locked in place properly.
chaisssos:
The "cap" was a temporary thing (and something I'd have in my tool box for any future leaks). Right now I've got the gauge set still attached and sitting in the cavity of the engine (above the exhaust manifold). But I can't drive it this way because the hoses will end up getting burned/melted by the manifold heat. A fitting/cap with valve (but no hose, ideally) would work fine.
I don't think I can use that puny 1" tool to tighten or replace the existing Schrader core. It's too small and the refrigerant is coming out with too much force. I can get the quick-connect from the test gauge on easy enough because it has substantial size. If THIS was the tool I'd be all set.
Who makes these tools? Don't they think of every possible scenario under which the tool might be used?
What if I wait to remove the gauge set from the port when it's a cooler ambient temperature? Do you think with a lower pressure I might have better luck??
I was able to remove the gauge set this morning without anything leaking out of the test port. It was only 72 degrees ambient (instead of nearly 90 on Monday), so the lower system pressure must've been the difference.
You replace the schrader valve the same way you would in a valve stem of a tire, unscrew the old one and screw in the new one. When I did mine, all the refrigerant had already leaked out so there was no need for a recovery system or vacuum pump. It only takes a few seconds.
I do not believe that the schrader valve used in a AC system is interchangable with the valve core of a tire, though they maybe. I could not get the valve core tool for tires onto the schrader valve of the AC, mainly because the neck of the tool wasn’t long enough, but at $3.49 for the tool and two valves, I don’t really care.
Now that the gauges are off the ports and the high-side port is stable (not obviously leaking), I'm going to try slightly tightening the core first to see if that stops the leak. I guess this means I'll need to buy a "sniffer" to make that determination? Is this a Harbor Fake item??
But if it turns out is IS still leaking and the core has to be replaced (and this is something that only "takes a few seconds"), is it possible to change out the valve while the port is leaking (say, on a 70-degree morning)?
Or is that too risky?
Keith,
You didn’t vacuum your system prior to refill?
The maker of the core replacement kit (A/C Pro) says in their directions that if the cores need to be replaced, the system must be completely empty and under no pressure first, then any remaining refrigerant needs to be removed using proper evacuation equipment before refilling and intalling new dust caps.
My feeling is that the valve problem was likely due to a canted valve core or one that had a piece of debris in it.
If you want to check for leaks on the cheap you might consider mixing up a thick solution of Dawn dishwashing soap and water. Swab some on the suspected leak. If it's leaking it will bubble up quickly.
Yes, a system should be evacuated before recharging it. However, it is possible to charge one without doing this but the results may or may not be as good as what you would hope for. Open the low side gauge valve a little and loosen the high side hose at the gauge set. This can bleed off some or most of the air in the system with the refrigerant purging the air out.
The main purpose of evacuation is to remove moisture anyway. Yes, the above method is kind of a "backyard hack" thing but it can work.
If the valve is leaking then yes the refrigerant will need to be removed before replacing any valves.
I just put a little spit over the port, it will tell me if it is leaking.
There is no need to evacuate the system, in my case, when I said the refrigerant had all leaked out, there was a little residual pressure but not much, maybe 1 or 2 psi. Since there was some positive pressure, I did not worry about air or moisture getting into the system. Even at zero psi, I don’t think that any significant amount of air or moisture will get into the system, especially with the cap on.
If your static pressure is under 30 psi, I don’t see any reason why you can’t just change the core. You won’t even loose that much freon. It is a little messy as some of the oil comes out with the freon. Other than being a bit oily, its the same as changing or inserting a valve core in a tire that is pressurized.
I strongly disagree that a service valve should be removed on a charged system. That could possibly lead to Stevie Wonder Syndrome, as in blind as a bat if refrigerant hits the eyes. (Assming no goggles are in use.)
Check THIS out ! Someone on another board gave me the link. Exactly what I need (for less than $40) ... except it appears by the 2nd review that this particular tool is for R12 instead of R134a (but he used it successfully anyway).
http://www.amazon.com/Mastercool-91490-Standard-Remover-Installer/dp/B000O823Z8/
I also found this at Mastercool's site:
http://www.mastercool.com/pages/valve_core_remover.html
So there are more than one type of R134a, too (standard, EATON, etc.). A "universal" kit runs a little over $100. The kits sold by type run about $55-$70.
Funny that yall mention a/c pressures on here, I got this nice high dollar gauge set for R-12 & R134a & never used the thing. I guess working at the dealership does have it's advantages like using that nice a/c machine they have so I no longer have to worry about buying cans again.
I would say if you got any buddies that work at a dealership, give them a holler. Makes it a lot easier to do things & quicker. Plus I have access to a lift which also is nice for my oil changes since I no longer deal with transporting used oil anywhere.