How to get a better seal on AC line mating surface?

[Klutch9]

My 2016 Explorer has two AC line connections in the rear of the vehicle that look like the one in the photo (for reference, not the actual part). They are located right above the driver’s side muffler and collect all the salt and dirt and, subsequently, are a failure point because of the corrosion. This spring I found that one of them had leaked and caused all of the refrigerant to be lost. So I cleaned all mating surfaces and replaced the o ring and washer with embedded o ring (see picture). However, a month or so later, one of the fittings developed another huge leak. Not sure what happened. I wire-brushed any corrosion away the first time, and also added some PAG oil to the o-rings, but maybe the mating surface is too imperfect to form a good seal.

Hypothetically… could I ‘assist’ the o rings with some RTV or something similar? I realize that this may make it impossible to take apart in the future and if that happens, I’ll just delete the rear AC. This is a work vehicle, and only I drive it. No passengers.

 

[JMJNet]

I read a tip a long time ago.
Use Nylog on the o-ring.
Nylog is the lubricant for AC o-ring.

I used Nylog a long time ago when I replaced the Compressor and Condenser coil on a Sienna.
I had it for 3 more years and it was good without any leaks.
I am just a amateur DIY, not a pro.

 

[ctechbob]

Not an AC professional in any way, but second the Nylog. It seems to be the most recommended thing out there. It is a lubricant and sealant of sorts.

I know it is sticky as all getout and you don't need much of it.

 

[chemman]

Nylog is the best!

 

[Chris142]

Don't use any sealer. If it's corroded you need to replace parts.

 

[Jetronic]

It's going to remain a headache unless all parts are replaced. Or deleted. If you are intending to keep the vehicle as long as possible, my advice would be to delete the rear evaporator and supply lines. If replaced, you get another few years, but at a considerable cost for no benefit.

 

[zzyzzx]

I read a tip a long time ago.
Use Nylog on the o-ring.
Nylog is the lubricant for AC o-ring.

I used Nylog a long time ago when I replaced the Compressor and Condenser coil on a Sienna.
I had it for 3 more years and it was good without any leaks.
I am just a amateur DIY, not a pro.

I also use nylog on the o-ring inside the service port caps. Yes, there are o-rings in there.