AC Schrader valve replacement (almost completely) without refrigerant loss.

Doing a Freelander service I discovered a slow R134a leak through a low side schrader valve. as I am not set up with the equipment to do major AC work so I ordered a tool to do it without out depressurising the system.

It arrived within about 4 days Chinese made so no instructions, but it was very low cost and it worked fine, the ball valve on the tool acts as an "air lock" you can extract the old valve through and insert the new one. Only trick bit is getting the old Schrader out through the ball valve as you have to use the system pressure to blow it out and it comes out like a bullet.

This is it connected to the low side of my dailly driver.

I didn't know there was such a tool!
So you unscrew the core and close the valve real quickly, then open it up and jam the new core back in just as quickly?

No need to rush it isn't like like changing a tyre valve, there is (almost) no pressure loss because it is all sealed up while you are working, the driver tool passes though the ball valve. The hole in the ball valve is also just big enough to pass the scharder valve through.

Once the old valve is fully unscrewed you close the ball valve and remove the unscrewing driver part of the tool tool. You then open the ball valve for less than a second to blow the old valve core out , it comes out through the ball valve like a bullet !!!!!!. Then with the ball valve closed drop a new core in on top of the ball valve and fit the unscrewing/screwing driver tool back on top. You then open the ball valve and push the new schrader valve through and tighten with the driver tool...............job done.

Even better!
Cool tool.

Mastercool makes a good one that has the large and small shrader valve core remover

www.mastercool.com/product/58560/