Can you change post size on a corny keg?

[kohalajohn]

Good morning all,

I ferment and dispense in corny kegs.

All but one of my kegs takes a 7/8 wrench to remove the post.

One keg, however, takes a 11/16 wrench.

It's a small annoyance, but it is annoying to have to search around for another wrench size.

I"d like to swap out posts so all my kegs were standardized.

If I bought 7/8 posts would they fit onto this particular corny keg?

 

[mac_1103]

Not likely because the different wrench size probably means a different thread size, but I suppose you might get lucky. You can figure this out pretty quickly by trying to thread one of your 7/8 posts onto the 11/16 keg. As usual, pictures would help, particularly of any markings on the keg.

 

[Broken Crow]

It all comes down to the thread sizes... Sounds like your kegs come from different sources and these things go back to the 1960's. The 'standard' thread sizes were 19/32" and 9/16" but even then, the nut sizes varied. If you can verify the thread sizes you have, you could try and match them up to replacement posts from the same vendor which likely come with the same nut size... but often the seller only mentions the thread size in the description: https://www.ontariobeerkegs.com/search.asp?keyword=ball+lock+post
Maybe I'm spoiled because I probably have a few thousand wrenches because I've been buying tools since I was 5 years old and can't imagine someone not having multiple wrenches in all sizes.... Just drop by Canadian Tire and grab an extra pair to keep with your brew-gear.

 

[kohalajohn]

Yeah, thanks you two, that answers it. It's easier to keep it as it is.

 

[Deadalus]

https://www.facebook.com/marketplac...f=marketplace_profile&referral_code=undefined
Great tool, I own one, not affiliated with seller.

 

[kevin58]

Also too there were many manufacturers of corny kegs and they did not all use the same size threads or fittings. I did a spring clean of all of my kegs once and took them all apart at once not knowing this. I ended up with several kegs leaking constantly because I had put the wrong posts on the wrong kegs.

 

[kohalajohn]

I use a

https://www.facebook.com/marketplac...f=marketplace_profile&referral_code=undefined
Great tool, I own one, not affiliated with seller.

aha. that's exactly what I'm looking for. thx

 

[kohalajohn]

I use a

Also too there were many manufacturers of corny kegs and they did not all use the same size threads or fittings. I did a spring clean of all of my kegs once and took them all apart at once not knowing this. I ended up with several kegs leaking constantly because I had put the wrong posts on the wrong kegs.

Yeah, I can see how that could happen. I remember in the bad old days before the interwebs, fiddling with all the keg pieces trying and failnig to block leaks.

I thought the only annoying issue nowadays was the two sizes of external nuts. I use deep socket wrenches, 7/8 and 11/16. But I see now the real problem is getting the inner threads mixed up.

Actually, there is anoher possible problem with deep socket wrenches. I was using a cordlesss drill.. One day I used my cordlesss driver instead. Big mistake. That torqued it down far with far too much force. A month later I'm trying to open it and no luck. The drill just clutches out and spins. I put a hand wrench on it and grunt and strain and nothing.

Finally I remembered the driver. Used that and broke it free.

I checked how much torque is actually needed and it is very little. I dialed my drill down all the way and the post held pressure fine. Then I just wrapped my hand aorund the deep socket and turned with just hand strength. Worked just fine. How about that.

 

[mac_1103]

The other problem that can come up even with posts of the same thread size is bottoming out before compressing the dip tube o-ring. "Universal" posts aren't really universal.

 

[kohalajohn]

Yeah, the lesson here is keep the posts with the keg they came with.

If the threads on the post and the keg match, they will hold pressure even with very little torque.

If I have to use high torque that is is a sign that I have a mismatch in the hardware.

And high torque causes problems. That time I over torqued with a driver, it tore the o ring, which had to be replaced. If I hadn't noticed the damage to the o ring, there would have been a mysterious leak, which would cause one to torque down even harder.

 

[bwible]

Also too there were many manufacturers of corny kegs and they did not all use the same size threads or fittings. I did a spring clean of all of my kegs once and took them all apart at once not knowing this. I ended up with several kegs leaking constantly because I had put the wrong posts on the wrong kegs.

Learned that the hard way as well. All keg parts are not interchangeable between different kegs

 

[tracer bullet]

For the wrench, you want one of these, but of course form a seller that has it. This was the link for mine but that was years ago.

https://www.amazon.com/dp/B088KB7D49?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_10

As for "does it work", it seems to me you currently have 7/8 posts on hand already, so, to try it out on the keg with 11/16" posts, isn't it as simple as just taking a 7/8 post you already have on hand and finding out?

I do agree not all things are interchangeable, but - as to trying it, isn't it that simple? You already have the parts, so go give it a shot?

 

[Deadalus]

For the wrench, you want one of these, but of course form a seller that has it. This was the link for mine but that was years ago.

https://www.amazon.com/dp/B088KB7D49?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_10

As for "does it work", it seems to me you currently have 7/8 posts on hand already, so, to try it out on the keg with 11/16" posts, isn't it as simple as just taking a 7/8 post you already have on hand and finding out?

I do agree not all things are interchangeable, but - as to trying it, isn't it that simple? You already have the parts, so go give it a shot?

No, not that simple. The thread sizes may be different and you could cross thread something. Sure, a person can be careful but if it happens to be close people sometimes keep cranking it down. I bought 4 recently new kegs for $50 but one was cross threaded and the other the seller had replaced a post already. Those two are both already annoying as the replacement post has an inside nut and I haven't even tried fixing the mashed threads on the other one. Still got 2 good ones for $25 each therefore but I have too many anyway so the screwed up ones will likely sit. Seller said they came with overly tight posts and he was too aggressive removing them.

If really wanting to change posts, identify the type of keg originally (ball or pin lock) and the manufacturer. That can tease out the thread size. Then look for a "universal" replacement. In quotes so that you know to match whatever threads are on the "universal" posts to the keg threads, because different keg manufacturers sometimes have different thread sizes. The "universal" posts have a fixed thread size and don't magically change it.

Many new ball lock kegs appear to be using the 11/16" size posts, which are also typically the same size as the "universal" posts but I'm not sure if there is any standardization occurring with the thread size itself. I'm thinking though that I did get a recently new keg that had 12 pt 7/8" size posts.

I had one of those wrenches you posted but the quality was poor and the ratcheting part failed.

 

[mac_1103]

The thread sizes may be different and you could cross thread something. Sure, a person can be careful but if it happens to be close people sometimes keep cranking it down.

If one was going to try this at home, my suggestion would be to remove the dip tube from the keg and the poppet from the post and try to thread the alternative post on by hand. If it gives you any trouble at all that probably means the threads don't match and you should stop trying before you ruin something.

 

[tracer bullet]

No, not that simple. The thread sizes may be different and you could cross thread something. Sure, a person can be careful but if it happens to be close people sometimes keep cranking it down.

I suppose it's relative then. I've got the mechanical and other DIY experience to not strip a keg post, and to recognize if it's too tight or too lose. I suppose there are those who would. So it could be simple to try, but with an asterisk regarding who's doing it.

 

[Broken Crow]

Posts aren't sold by wrench size and on amazon, many don't even list the thread size.
Here's some of the important specs:
Cornelius Spartan & Super Champion: Gas 19/32” – 18 Liquid 19/32” – 18
Cornelius R (pin lock): Gas 19/32” – 18 (2 pin) Liquid 19/32” – 18 (3 pin)
Firestone V Challenger, Firestone VI Challenger, Firestone Super Challenger: Gas 9/16” – 18 Liquid 5/8” – 18
Firestone A, Firestone R, John Wood RA, John Wood RC (pin lock): Gas 9/16” – 18 (2-pin) Liquid 9/16” – 18 (3 pin)
John Wood 85, Firestone Challenger: Gas 11/16” -18 Liquid 3/4’’ – 18
Here's a nice .pdf that someone put on this site years back: https://cdn.homebrewtalk.com/data/attach/584/584404-Keg-Thread-Sizes.pdf
Kegoutlet informs us that Torpedo kegs have the 19/32" thread and OBK tells me that my Kegland and AEB kegs and the cheap chinese kegs available under various names also have the 19/32" thread https://www.ontariobeerkegs.com/5aeb-dual-handle.html https://www.ontariobeerkegs.com/5aeb-dual-handle.html https://www.ontariobeerkegs.com/ob-keg-5gal.html
Posts are not sold by wrench size because that is not the important part.
Without shaming anyone, there are 2 types of people that need this information: Those who use tools every day and those who don't. Many on this site only DIY when they have to and thier perspective may differ. A wrench or socket takes up very little space and when you need multiple sizes, simply have multiple sizes.
For those that may not know how it should feel: First; when it comes to used kegs you may have filthy threads. When you disassemble your posts on used kegs for the first time, use a wire brush to clean the theads. When you go to re-install or replace, do a test first: Do not put the poppet in, just turn the post down all the way and back off by hand..if there is any resistance, there is a problem.
Here's a complete set of replacements from a reputable seller (who doesn't list the nut-size because that's not the important part):
https://www.kegoutlet.com/how-can-i-tell-what-type-of-posts-will-fit-on-my-corny-keg.html
Just sayin...hey it's Monday...I don't like Mondays.