Keg gaskets, sealing gaskets and leaks

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RichBenn

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I have mostly used Pin Lock kegs, and am converting posts to ball lock As well as starting to ferment under pressure. That’s when I noticed I had some bad seals, one on a keg lid(even with lube!) and one on a post. There “may” be others, as they are old. So I need to buy new. But which ones?

I’ve always pressurized my kegs to 30 PSI to get a good seal then bled them down to serving pressure. I’d love to have the keg lids seal without doing that. Ideally, I’d like to have the keg lids seal with zero pressure for pressure fermenting in the keg.

Will just new keg seals(and post o-rings)get me there? If so, which ones? I see regular, silicone, and some quite expensive oversize o-rings at Williams Brewing that are supposed to work…

EDIT:
I am asking SPECIFICALLY for experiences with KEG lid orings brands at LOW pressures.
 
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I use regular keg lid gaskets, new ones with no issues even at the 30psi you are using. If you are using new gaskets and still have sealing issues check around the lid and the keg part for issues. Mix a soapy solution and spray around the kid lid and the posts. Dip tubes, posts or the lid could be sources of a leak.

If you check out "Homebrew Finds" they have had lots of info on rebuilding kegs and the gaskets needed plus links to where to find everything. Vaulebrew is one spot that comes to mind but there's a whole bunch of others and regular contributors here on HBT.

On my PC I keep a directory of helpful stuff on brewing, etc.
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No, I’m NOT using 30 PSI and I’m not asking for information on other orings(I’ve bulk quantities of those.) or asking how to diagnose leaks.

I am asking SPECIFICALLY for experiences with KEG lid orings at LOW pressures.
 
I see regular, silicone, and some quite expensive oversize o-rings at Williams Brewing that are supposed to work…
One of those oversized o-rings fixed one keg I have that wouldn't seal. Now it seals airtight at 0 PSI. I do have to make sure that the lid is aligned in the opening correctly and lift the keg by the bale to get the o-ring to seat properly. They cost two bucks more than a standard o-ring. Personally I don't think that's very expensive, and I'm a notorious cheapskate.

Also, try the decaf.
 
One of those oversized o-rings fixed one keg I have that wouldn't seal. Now it seals airtight at 0 PSI. I do have to make sure that the lid is aligned in the opening correctly and lift the keg by the bale to get the o-ring to seat properly. They cost two bucks more than a standard o-ring. Personally I don't think that's very expensive, and I'm a notorious cheapskate.

Also, try the decaf.
It’s more the shipping than the 2 bucks, as Williams is not where I normally get stuff. I had an order in a cart elsewhere for 5 complete gasket kits for $8 shipping included., so it is a bit more. But if it fixes the problem without buying brand new kegs(I have a lot of them), then maybe it’s worth it…
 
It might be in my head, but the white O-rings for the lids seem to be thicker and thus seal better at lower temps than the black seals. Also, just to get the obvious remedies out of the way, have you tried rotating the lid 180 degrees to see if it seals better? Or hold the lid in place then hit it with gas (at serving pressure) to see if it seals? The latter has worked for me before as pressure will 'pop' the lid in place. Then I latch the lid close.

As for pressure fermentations, I don't back my kegs down to serving pressure at the beginning. If the lid sealed at 15, 20, etc. I just leave it there. The spunding valve will exhaust any excess pressure.
 
white O-rings

Silicone. Usually considered bad because O2 permeates through them. Each person has to ask if it's at a rate they care about or a beer that shows the effects (drink a keg of stout in a week - no problem, drink a keg of NEIPA over 2 months = yep a problem).

When I had issues it was either 1) lid o-rings were old and brittle, or 2) the lip of the keg itself was dented. Lids always seemed fine but used kegs seem to get really beat up for some reason, Usually some pliers did the trick.
 
Silicone. Usually considered bad because O2 permeates through them. Each person has to ask if it's at a rate they care about or a beer that shows the effects (drink a keg of stout in a week - no problem, drink a keg of NEIPA over 2 months = yep a problem).

When I had issues it was either 1) lid o-rings were old and brittle, or 2) the lip of the keg itself was dented. Lids always seemed fine but used kegs seem to get really beat up for some reason, Usually some pliers did the trick.


I have a few kegs with the white Orings. I never even gave it a thought they might be silicone. The last few batches, particularly hoppy beers, seemed off after a couple of weeks. They were still drinkable, but didn't taste the same after that first pour. Now you got me thinking.

Off topic, but are the black seals EPDM? Can I boil those to sterlize if I can't readily replace them?
 
No, I’m NOT using 30 PSI and I’m not asking for information on other orings(I’ve bulk quantities of those.) or asking how to diagnose leaks.

I am asking SPECIFICALLY for experiences with KEG lid orings at LOW pressures.
Sorry for trying to help

I know you are not using 30 psi, I could figure that out from your post.

In my experience, regular new keg orings work just fine, that's all I use.
 
I have not had good luck with silicone lid gaskets ( at serving pressure to be clear). They seem to be too soft at lower pressures.

I got some included with new lids. They are white and get swapped out with my stock of black ones that I know are not sillycone. Not sure what the black are made off.
 
I think black ones are buna-n. Kegland has dropped the silicon ones because of oxygen permeability, replacing them with a yellow one that they tested in a lab.

i’m hoping to find something that I can trust without doing a two day test every time I use it. Supposedly new lids don’t have the problem, and the Williams thick ones are supposed to work well with older kegs. So I’ll start there and run some tests.
 
For my ball lock Cornies...

Keg lids I use the plain old 70 durometer buna ones (AS568-417) from McMaster-Carr. Seem to work for me. 🤷‍♂️


Also got buna square o-rings (AS568-109) for the dip tubes and buna quad seal o-rings (AS568-111) for the ball lock posts there too.

Note the o-ring numbers are trade sizes, not McMaster-Carr part numbers.
 
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I’ve had similar issues with some old kegs that I acquired. After cleaning and replacing o-rings, some of them would leak at the post or lid. Swapping lids and posts with another keg usually solved the issue. I know that it sounds crazy but it is the only solution that worked for me.
 
Look really really hard at the lid flange to see if they have any dings, bends, etc.
While I *KNOW* you are not looking for o-ring advice, those white oversized ones from Williams Brewing were the only solution for me with a couple of second hand kegs I bought.
 
Look really really hard at the lid flange to see if they have any dings, bends, etc.
While I *KNOW* you are not looking for o-ring advice, those white oversized ones from Williams Brewing were the only solution for me with a couple of second hand kegs I bought.
They do the trick until you realize those stupid rubber feet on the lid closure are worn too! Had that happen on a couple of kegs after using the big white o-rings. I added a penny under and all sealed up
 
Look really really hard at the lid flange to see if they have any dings, bends, etc.
While I *KNOW* you are not looking for o-ring advice, those white oversized ones from Williams Brewing were the only solution for me with a couple of second hand kegs I bought.
Interesting. I found out that pin locks need a fatter gasket than ball locks. Some sell them without specifying, which may be the problem for some. Since I’m converting to ball locks, new o-rings have solved those problems.
 
They do the trick until you realize those stupid rubber feet on the lid closure are worn too! Had that happen on a couple of kegs after using the big white o-rings. I added a penny under and all sealed up
Fortunately, I’ve already done the feet. I guess one has to replace “everything” on (very)old kegs to have some hope of success.
 
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