questions on keg o-rings

[twd000]

I need to stock up my supply of o-rings to keep on hand for my kegs.

I see there are silicone and Buna-N options - sounds like silicone is preferred because it's softer and compresses more?

I have a variety of kegs - Cornelius, Firestone, ball-lock, and pinlocks converted to ball-lock. I assume the post o-rings are universal/interchangeable, but just want to confirm.

What about the liquid and gas dip tube o-rings - are those universal, or are there different sizes? I use a floating dip tube in several kegs, which means I have replaced the original liquid dip tube with a gas dip tube in the liquid post. I bought the gas tube from AliExpress and I have had some intermittent issues with foamy pours. I wonder if it is not sealing completely and letting gas blow past the o-ring and mix with the beer when pouring?

Here is the product (US $4.3 25% OFF|NEW 2pcs Homebrew Stainless Steel Dip Tube Gas in for Draft Beer Cornelius Corny Keg|homebrew stainless|dip tubehomebrew stainless steel - AliExpress)
I notice it shows both o-rings on the post, but I have only used the smaller one. Maybe I need to try the fatter o-ring to see if I get a better seal

Who's got the best online price on a couple dozen o-rings?

 

[Transamguy77]

I don’t think you are supposed to put them both on, that kind of defeats the purpose of the o ring, it’s designed to flatten and fill in any imperfections in both sealing surfaces.

I purchased some o ring kits on amazon, I think I bought 10 sets for $10 and they came with both ball lock and pin lock o rings.

Edit: I found the link.
Universal Kegco Type O-Ring Ten Gasket Sets for Cornelius Home Brew Keg and Homebrewed With Pride keg sticker https://www.amazon.com/dp/B0105JYK9C/ref=cm_sw_r_cp_api_i_qxO1EbW78128P

 

[twd000]

I don’t think you are supposed to put them both on, that kind of defeats the purpose of the o ring, it’s designed to flatten and fill in any imperfections in both sealing surfaces.

I purchased some o ring kits on amazon, I think I bought 10 sets for $10 and they came with both ball lock and pin lock o rings.

Edit: I found the link.
Universal Kegco Type O-Ring Ten Gasket Sets for Cornelius Home Brew Keg and Homebrewed With Pride keg sticker https://www.amazon.com/dp/B0105JYK9C/ref=cm_sw_r_cp_api_i_qxO1EbW78128P

yes that photo showing both o-rings is confusing because it should only be one. Maybe the fatter one would seal better?

Thanks for the link. I guess I only need ball-lock o-rings because all the pinlock kegs I own have been converted to ball-lock posts

 

[twd000]

I just came across this option. A square-profile o-ring for the dip tube, instead of round. Anyone tried this one?

https://www.homebrewing.org/Square-Dip-Tube-O-Ring-_p_9320.html

 

[passedpawn]

Yes go withe the Quattro. Much better seal. I have them on dip tubes.

 

[day_trippr]

Many cornelius style kegs originally came with quad seal dip tube rings while the post O-rings were always round (easier to fit the QDs).

Be aware that silicone O-rings are not compatible with silicone keg lube and will eventually start to dissolve and leave residue inside the QD.
Otoh, Buna-N is highly resistant - but not immune - from the same lube but instead of melting they will swell and you'll notice QDs are harder to get over the post and to remove after a couple/few years.

I buy Buna-N post O-rings by the 100 lot on Amazon and don't hesitate to replace one if it even looks at me wrong

Cheers!

 

[twd000]

thanks for the input I'll order a couple 100-packs of o-rings to keep on hand

Now I'm eyeing the quick disconnects themselves. I have never disassembled them to inspect the internal o-rings. Is it possible that a failed seal internal to the QD could allow gas to flow past and enter the liquid stream, causing foaming? I should note that I don't have any leaks (liquid or gas), just a foaming problem on some kegs/taps

I haven't been treating the QD's like a regular maintenance item, do I need to?

 

[Transamguy77]

I have taken the QD’s apart to clean them every once in awhile and I lost an o ring, Adventures in Homebrewing has repair kits so I bought a couple of sets with my last order just in case that happens again.

 

[day_trippr]

[...]Is it possible that a failed seal internal to the QD could allow gas to flow past and enter the liquid stream, causing foaming?[...]

I don't think that can happen, as there's only beer coming out of the post.
What can happen is if the small dip tube o-ring for the beer side is missing or damaged, then CO2 from the headspace can (will) be injected into the beer stream inside the Out post. The "spitting foam" syndrome is a classic indicator.

I never do much with my QDs. The beer ones get cleaned internally when I do a recirculating cleaning cycle ever so often, but that's about it. I have a couple of dozen CMB QDs in service and the only one that ever failed was the gas QD I used for purging kegs and CO2-push transfers, that I had accidentally plugged on beer posts too many times and had literally stretched the inside of the QD to where it would not reliably seal. That took years to happen though

Cheers!

 

[passedpawn]

thanks for the input I'll order a couple 100-packs of o-rings to keep on hand

Now I'm eyeing the quick disconnects themselves. I have never disassembled them to inspect the internal o-rings. Is it possible that a failed seal internal to the QD could allow gas to flow past and enter the liquid stream, causing foaming? I should note that I don't have any leaks (liquid or gas), just a foaming problem on some kegs/taps

I haven't been treating the QD's like a regular maintenance item, do I need to?

I rarely clean mine (though it's so easy to open and soak overnight. When I did open them, they are always suprisingly clean. So I'd suggest only once a year, for peace of mind. At least that about the timing I'm on. And I have peace of mind (as much as one possibly can during the panic-riot-demic).

 

[KartRacer54]

I found out the hard way that pin lock kegs use a slightly larger o ring. Found that on this forum. Replaced all my newly replaced and leaky smaller o rings with the larger ones and problem is resolved. Bought pack of 100 from Amazon #112 for $6. 23 - 1/2 x 11/16 x 3/32

 

[Tobor_8thMan]

Pin lock o-rings are different than ball lock o-rings. See

http://www.homebrewtalk.com/threads/gas-side-pin-lock-leak.682170/