Gas side pin lock leak

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mtrogers14

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I have a pin lock system and am at the end of my rope ! I am tearing through co2 because for some reason the gas post on my pin lock keg will not seal when connected to disconnect. I have tried everything, new posts, new o rings, multiple disconnects and nothing helps. I just put some Teflon tape on the post over the o ring and it seems like that may have done the trick. My issue is I like things to work as they should. Any idea why this is happening ? Should I convert to Ball lock ? Are they better ??
 
Ball lock vs pin lock. No, other than the connections (pins) they are the same. Both QDs push into the post poppet.

Sounds like the QD is not fitting properly on the post. Putting normally unneeded teflon tap on the post is getting a better seal/seat. Try a different QD.
 
That is exactly what I was thinking. What is a reliable place to get true pin lock o rings. Obviously the site I got them from is not as legit as most would assume
 
Legit pin lock post O-rings are thicker than those for ball lock posts. Using the latter on pin lock posts will cause an unreliable seal that merely cocking a gas disconnect slightly can reveal...

Cheers!


^^I agree that this is probably a good place to start.
4BA7E65E-EB2E-4BB0-B6D1-672530A05961.jpeg
Pin lock: left
Ball lock: right
Keg lube is your friend too.
teflon on the post threads probably isn’t doing any good, the dip tube o ring is what should seal that connection.
 
The OP didn't tape the threads, but draped/wrapped the post itself.
I'm betting the teflon served to increase the effective OD of the post O-ring...

Cheers!
 
Understandable, that's literally the first time I've ever read of anyone even trying that :D

Cheers!


LOL, i pipe taped my posts back before i started vasolining the o-rings......was going through 20lb's of co2 every other month......desperate.....

edit: to the OP, could it be the PRV valve? i find they tend to leak a lot also....gotta vas them a few times a year also....in my case of 20lb's every couple months it turned out to be the PRVs....pipe tape on the post was pointless....
 
fwiw, stock pin lock kegs - if they had a PRV at all - typically came with "single-use" PRVs that were essentially "burst disks".
I don't think there was ever an oem pin lock keg manufactured with a self-resetting/manual PRV. That takes a lid swap...

Cheers!
 
fwiw, stock pin lock kegs - if they had a PRV at all - typically came with "single-use" PRVs that were essentially "burst disks".
I don't think there was ever an oem pin lock keg manufactured with a self-resetting/manual PRV. That takes a lid swap...

Cheers!


i only have two pin locks, and the other 4 are balls.....first pin lock was the one i think was leaking....they do use different PRVs...much shorter......

but to the OP, have you tried replacing the lid for the keg"s"? i got a ball lock lid that works fine for my pin lock keg.....
 
Problem is certainly the gas post, I can hear it leaking. More than half way through a 10 lb canister I got this afternoon. Makes no sense to me to me at all.
 
what kind of QD? flare, or barb? does it leak when disconnected? i'd disconnect between pours if otherwise.....
 
Does not leak when disconnected. And barb I believe


i just wondered how you know you're half through the tank? as far as i know unless you weigh it, it's empty when the gauge goes down......

edit: i've had luck vasoline for lubing my posts, pipe tape didn't work......keg lube is available also.....
 
I use these from Home Depot and don’t have any trouble.
04D5A530-3DAD-48F5-99F2-AEFDD3DCDFE9.jpeg


Edit: the dimensions for ball lock o-rings are 5/8”OD X 7/16” ID X 3/32” if you have an accurate way to measure the ones you have.
 
I had a leak a few weeks ago. Replaced the gasket and problem solved. Try a slightly thicker gasket then the one you currently use.

But in the mean time, until you solve the issue, turn off your gas at the tank when not serving to limit wasting CO.
 
I have a gauge that shows how much gas is left. Curious, is it possible that my QDs just need to be replaced ? Do they wear out over time ? They are pretty old.
 
is it possible that my QDs just need to be replaced ? Do they wear out over time ? They are pretty old.
There’s really nothing that could wear out unless they have bad scratches inside for some reason. I have some I got from a repair technician for Coke that are at least 20 years old and most likely older than that, that still work perfectly. I still think it’s an o-ring problem, which will be the cheapest repair if you can source them without a large shipping expense.
 
I have a gauge that shows how much gas is left. Curious, is it possible that my QDs just need to be replaced ? Do they wear out over time ? They are pretty old.
Guage only tells you the pressure, which is dependent on temperature, not level, as long as there is any liquid CO2 in the tank. it's only at the very end, when it's all gas, that the guages tells you anything about how much is left in there. But if you are going through 20lbs tanks every few weeks, there is definetly a leak. I last filled my 20 lbs tank probably 2-3 years ago.

The only reliable way to tell how much CO2 you have left is to go by weight.
 
Well I have dip tube o ring info but can’t personally verify it. Check out 109-70D. It was recommended by this extremely helpful post from a ways back. I bought a pack but I was using up a bunch of normal looking o rings so haven’t got to them. But today I’ve got a leaking keg on a Brown Ale and my guess is the dip tube o ring....
 

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So not leaking without the QD on, the correct o-ring on the post is a good suspect. A more outside possibility is do you have the internal o-rings for the QD in there? If you never knew they were in there they are easy to wash down the drain. Also, do you have barbed QD's or the screw-on flare fittings? The screw-on ones I find need to be held with a wrench and then hand tightened vs just holding with your hands to tighten. And then check your tubing clamps.

Some of the keg rebuild kits will include both ball and pin lock o-rings for the posts. With those you'll see the difference but maybe clearly mark and put away the ones that don't work. They are often color coded in the kit.
 
OK I am about to abandon keging and go back to bottles !! I have replaced EVERYTHING and my results are as follows...........
New o rings (yes the correct o rings) brand new disconnects and just so happens in a newly converted keezer, Carbonated my latest brew, all went well. Left in the keezer for approx 36 hrs, no problems. Went to the basement on an unrelated matter and noticed the O2 tank was covered in frost........must be a leak. Opened the keezer and sure enough gas side leaking again !!!! I am very handy, do most things myself and have been brewing for years. I can not imagine what the problem is anymore and I am about to give up !!
Someone please give me an idea where to go from here
 
First thing when you think you have a leak is to shut off your Co2 daily until you find it. If you have leak then it is from the bottle to the valve and valve to and including the keg. Try pressuring just the keg itself, then pull off disconnects. Let it sit overnight. If no pressure it’s the keg. If you have pressure on keg still it’s from the qd to the valve. In this string you have the qd fit to post, the clamp on hose + swivel if you have them and the clamp on nipple on other end of hose. To check the qd itself + clamp and swivel submerge all this in water and you will see bubbles if anything leaking. Spray other end of hose with soapy water to check that clamp and nipple connection.

if leak was on the keg spray post,prv, and lid oring with soapy water. You’ll see it if leak is there. Next and harder to checL is the dip tube o rings. Invert keg and put in 5 gal pail of water. You should see bubbles if keg pressured and dip tube orings are bad.

so I just had a cylinder go down a 20# no less. This is my working one for force carbing kegs. I left the valve on by accident. It has two lines to a ball and pin lock disconnect. My leak was at the regulator body. The body is threaded so the guts can be changed.It somehow was loose. That’s why you’ve got to check everything.
 
I feel like the issue is the connection between the QD and the post for some reason
 
I feel like the issue is the connection between the QD and the post for some reason

I know you mentioned this several times earlier, but are you 100% that is where the leak is? If your cylinder is icing up, it is a very large leak and should easily be seen.
Do you have a way to submerge the entire keg while it’s still hooked up to the gas? Fill a trash can or barrel with enough water to cover everything and look for bubbles. If it truly is the gas side connection, you can then decide if it’s the connection or the keg by unhooking the QD and see if bubbling stops.
Is this system new to you and do you have any other kegs with similar problems?
A leak large enough and fast enough to ice the cylinder doesn’t seem like it would be after the regulator to me. I don’t know what kind of regulator you have, but do you have a nylon washer 9312FDC2-F0D4-4151-AA40-28E19A4D0C66.jpeg
between the valve and regulator stem. (Some regulators have a built in o-ring and the washer is unnecessar
 
i can say this for sure, i could hear the leak in the area of the post, when I disconnect the QD the sound stops
 
Man... I don’t know what else to say/ try. If you’ve replaced everything and tried multiple combinations, I’m stuck.
Last idea. Are you using any lubricant on the post o-ring before you attach the QD?
 
is the screw on thing tight on the QD? it unscrews and screws on.......you can convert it to ball lock i believe.....(and damn, when i was going through a 20lb'r every month i wish i could remember where i found the leak, i just thought it was normal for a while.....)


when a keg is carbing it will hiss a bit when first turned on......if it sits and the pressure equalizes with out more pressure.....


I have a gauge that shows how much gas is left.
The only reliable way to tell how much CO2 you have left is to go by weight.


there's usually a TW stamp on the tank telling pounds empty....if the 'guage' is going down it's empty, and when it's empty it goes down FAST......swap it...weigh it, i keep mine on a scale, i use about an ounce a day carbing 2-4 kegs and serving a gallon....
 
Have you sprayed a soapy water solution to find the exact spot that’s leaking? Can you pressurize the keg and remove the disconnect and see if the keg holds pressure?
 
I picked up a couple 3 gallon pinlocks and they definitely take a different oring. I was getting turbulence or sucking in air on the liquid side and bought some pinlock specific ones from Adventures in Homebrewing. I can't say yet if they fixed my problem, as I haven't had to use one of the pinlock kegs yet.
https://www.homebrewing.org/Post-O-Ring-for-Pin-Lock-Keg-_p_2501.html
 
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