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Schrader valve replacement tool

Hello; Has anyone used the tool that allows you to remove and replace the AC Schrader valves without evacuating the system?

Yes, I have. But, when you have a leaking schrader valve, chances are that the system pressure is pretty low so it can be done, just do it when its cold outside and you have not operated the car. That’s when the system pressure will be at its lowest. There will be leakage but it can be done.

The valve is holding lots of pressure - I think the seal (o -ring) around the bottom of the valve has a tiny leak because I see a little green dye. Also I am in Florida so its NEVER cold LOL If I let the pressure out of the system and change the valve won’t air get in? Do you recommend having the system evacuated at a repair shop - is that necessary? Thanks for all of your help, patience and expertise.

By cold, I mean in the morning and the car has not been run. The pressure in the system will equalize to about 30 psi, about the same as a tire, lower if it has been leaking for awhile. If you are quick enough, all the refrigerant wont get out so air will not get in. Wear gloves, the escaping refrigerant will freeze your hands.

It would be best to have a shop do this job, it should ask too much. You can always get estimates.

OK gotcha; thanks so much! “IF” air gets in will it cost more later if i have to take it to a shop? Thanks for all of your help and patience!

The pressure will be considerably above 30 psi if the system is fully charged unless the temperature is below freezing.

A non-operating A/C with a normal charge will usually have around 120 PSI of pressure in it. This can really come back to bite you if you’re not at least semi-knowledgeable in A/C repair; meaning frostbitten fingers or face or even permanent blindness if refrigerant hits the eyes.

Short of that Schrader valve tool, it would be best to let an A/C expert handle this because the system, if opened up, will need to be evacuated and recharged.

One thing that can cause a valve leak sometimes is that the valve may get canted a bit or have a tiny piece of debris in it which is not allowing the valve to close fully. Sometimes a few short and very sharp raps with a small hammer on the side of the valve assembly may jolt things into place. A drop of liquid dish soap on the valve before doing this will let you know if it worked or not; and by rap I mean tap, not whale on it.

OK Thanks; I think it may be the seal on the valve?

ALWAYS wear eye protection when servicing A/C…Just one drop of liquid Freon in the eye is all it takes…

Any chance that dye you see on the valve is what was left there when the dye was added to the system, the gauges disconnected, etc?
Dish soap would rule that out.

I purchased one of these to swap out the Schrader valves without dis-charging my A/C system. Unfortunately, it doesn’t work for my Ford truck because Ford uses a high-flow valve, not a standard Schrader valve. Worked great for my Toyota, tho.

Thanks; do you think it will work on a Saturn?

I added the stop leak w/dye in it; the dye is showing up around the upper end valve

Thanks for the safety advice I appreciate it! p.s if I try to tighten the valve to see if its loose - its a a normal clockwise thread NOT a reverse thread? just checking

Exactly how does the tool work? How does it remove and replace the valve without the system leaking

you tube valve core removal tool. it is simple and ingenious. Like separating chambers and isolating your issue. check it out.

OK Thanks!

also; will the tool work on the UPPER A/C valve (high pressure)

Normal clockwise thread. If the system is not running, the pressure in the high and low sides will be the same. The cooler the system is, that is weather wise and under hood temperature, the lower the pressure. Its best done early in the morning before the car has been used. Also less wait time at the ER, just in case.

I’m going to go all the way back to my original comment when this subject first came up - which was just that this isn’t a DIY thing. Just my opinion.