Slow leaks from Corny Kegs

[HB2 HughBHomeBrew]

I have several 5 gallon ball-lock Corny kegs - new ones from Adventures in Homebrewing, less than a year old.

Some of them leak, and it's a really slow leak. I had checked everything with soap and thought all was well, but noticed I was losing CO2 from the tank faster than should, with three kegs on a 5lb tank. No leaks to be heard or seen with soap. Turn off gas at regulator, come back overnight or a few hours later and 2 out of 3 kegs start having CO2 flow when I turn back on - the other is fine. (The beers are carbonated already - its not flowing because of that).

I have checked these two with soap to 30 PSI - no leak to be seen. But one of them, after it was kicked/bottled, I pressurized to about 14 PSI, disconnected gas, soaped it up, and overnight there were 3 little areas of dried tiny bubbles around the big opening. So, a very slow leak at top I guess, but so slow it can't be seen at 30 PSI with soap. I have two kegs acting this way and it's really annoying to not be able to find a leak without letting it sit overnight and lose gas. I understand that changing O-rings might solve problem, but these are new kegs/rings, and you'd think I'd be able to check them without having to let them sit overnight. Plus, they have beer in them already.

Thoughts? Is this just part of life with Corny kegs - that some have slow leaks?

 

[@RoyalGallon]

Do you ‘grease’ the O-rings. I use petroleum jelly smeared on the big O-ring and get a better seal than without.

 

[Harleybrew32]

I had a few leaks on 2 of my kegs, I replaced the o-rings and do to following, after I kick a keg, I clean it, I take everything apart, poppets, tubes and o-rings, also the lid relief.
soak in PBW or Oxiclean(unscented) in warm water for a few hours. then rinse them with hot water.
sanitize everything and put some keg lube on all the o-rings.
see if lubing up those O-rings helps your problem.

 

[AJinJacksonville]

What Harley said...

 

[odie]

new o-rings and keg lube

 

[brew703]

I've had issues with the o-ring on the liquid post. For some reason, when tightening down the post the o-ring gets cut, either by the threads of the keg post or the dip tube.
Wherever there is an o-ring lube it up. You can also get over-sized lid o-rings from Williams Brewing. Those work really well.

 

[Jocky]

Definitely recommend lubing up the seals. It helps them seat better.

Aside from that be sure it's the lid leaking, and not something else (e.g a disconnect/small split in hose).

 

[VirginiaHops1]

The best way to seat the lid is to turn on the gas and let the pressure seat it before you snap the legs down, vs snapping the legs down and then turning on the gas. I've found with my old used cornies the lid can leak a little if I don't do that. I use torpedo kegs now as my serving kegs and they've seemed bullet proof so far.

 

[Dr_Jeff]

Before I started doing closed transfer and fermenting under pressure, after racking the beer into the keg, I would lift the keg by the lid handle/bail and hit it with 30-60psi to set the lid. Minimizes sealing problems. It worked for me, everyone has their own method and what they think works best. Sometimes, I would hook up the gas prior so setting the lid so that gas is going in, purging the headspace and then lifting by the lid handle, setting the lid. I rarely had leaks doing it this way.

 

[The_Bishop]

I can't say enough good things about silicone keg lid rings. I used these:

https://www.amazon.com/417-Silicone-Ring-Durometer-Pack/dp/B07R738FXK