Kegging - used kegs, cobra tap not dispensig

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jwplessner

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I hope someone can help--going through a lot to figure out this problem.

I purchased four used kegs locally, non-reconditioned but with a perlick serving tube with cobra tap. I filled each keg with water, got the gas disconnect on and added 20 psi pressure, then tested the pressure both by turning the release valve and by manually pressing the poppet in with a piece of plastic. Each keg holds a seal and has more than enough serving pressure to push the water out when testing the valve.

However, when I connect the cobra tap (and engage the trigger), nothing comes out. If I put A LOT of pressure on the OUT quick disconnect, I get little dribbles out of the tap but not much. This leads me to believe that the quick disconnect is not pushing the poppet in. Replacing and lubing all o rings in one of the kegs did nothing. I did not interchange the in and out connectors, and the notched connector is in the gas IN connection point.

I want to rule out poppet failure because this is happening on four different kegs. I tried another quick disconnect on the cobra tap but same results. It's almost as if the disconnects are the wrong size, but they are the black ones (as opposed to the gray attached to the co2 hose).

Any advice is greatly appreciated; thanks.
 
Pictures of the posts and disconnect?
Did you try another length of beer line to rule out clogs?
What happens if you depress the poppet manually, using a key or screw driver?
 
Which poppet are you manually pressing to test? If you push on the poppet in the liquid out post does water spray out? If not, there could be a clog in the diptube, or the diptube could jammed against the bottom of the keg, or it could be the wrong type of poppet for that post. If water does spray out, then I'd check the cobra faucet. Sometimes they get a small piece of plastic from the molding process stuck inside of them, which can block the flow. Did you possibly mix up some of the poppets cleaning and replacing o-rings?
 
Opening up the out valve manually results in water spraying out with lots of pressure, not just a trickle. I tried multiple QDs to make sure there wasn't a clog there and checked the hose for clogs; I can push air through.

Pictures of the QDs locked in place and of the out valve attached. Whether or not I have a cobra tap on the out end, I get no output, or just a little if I put my body weight on the qd.

image-724536123.jpg
 
With that black QD on there, and no tubing attached, you don't get beer spraying out? But you do get a spray when you push down on it manually?

If so, take the black QD apart. Do it over a white piece of paper, because there are four little parts that are hard to find. (ask me how I know). Use a screwdriver, and unscrew the top. Remove the parts. There will be a spring, a pin, and a black o-ring that may be sort of stuck to the top or inside, plus the top. Rinse it out and inspect it for a clog.

Edit- I see you've used multiple QDs, so that must not be the problem. In that picture, I can't see the base of the post. Can you take another pic? And let's see the other one, too.
 
Thanks, pics attached.

Is there a way to test a QD without a working system? I'm not so sure I'd be successful taking one of these apart.

image-4073422477.jpg
 
Hmmm, the post on the right is the gas post and the one on the left is the "out" beer post. Is that how they are on the keg?

Taking the black QD apart is simple.

To take off the post, you just have to take it off with a wrench. I bought a deep socket set to make it easier. But you should always take apart your kegs to clean and sanitize, so it's better to learn how to do it before you put beer in it anyway. Might as well start now!
 
Tons of videos on YouTube to detail how to break down and clean every keg known to man.

I would inspect your keg before playing hokie-pokie with the QD's.
 
Thanks guys, I cleaned and replaced the o rings first thing. Thought we were talking about opening up the qd fitting attached to the hose. I checked and switched out the poppets and posts in the keg itself, multiple qd pieces, etc., to no avail. Unless there is further advice I will replace the posts and poppets. This is happening with the two Cornelius super champions i acquired but not with the Firestone challengers.
 
Any time I buy a used keg I break it down completely, clean and sanitize it, replace the gaskets on the poppets, lid, and dip tubes - then I test it out.
 
jwplessner said:
Thanks guys, I cleaned and replaced the o rings first thing. Thought we were talking about opening up the qd fitting attached to the hose. I checked and switched out the poppets and posts in the keg itself, multiple qd pieces, etc., to no avail. Unless there is further advice I will replace the posts and poppets. This is happening with the two Cornelius super champions i acquired but not with the Firestone challengers.

Same QD's work on the challengers but not the super champions? If so then I think we've narrowed it down to having the wrong type of poppets. This also makes sense based on your description of being able to get a little flow when you put your body weight on the QD. There's almost never a need to replace the posts, just replace the poppets with the correct type. For super champions you need them to look like #2 from the picture-

Poppets%20-%205%20lineup.jpg
 
I would agree that's it's probably the wrong poppets. Remove them and post a picture here.
 
I resolved this problem by following advice I found in another thread; thanks to day_trippr. The trick was getting the QDs seated onto the post; they just weren't going on until I lifted up the QD ring, pushed the QD onto the post, and then released the ring. This is the case with every post, I'm not sure why. After that, CO2 fill and dispensing are normal.

Clearly you have pressure on the regulator and the regulator is dialed up to 30 psi, so the problem is at the keg connection. I agree the most likely problem is you don't have the gas quick disconnect actually seated all the way down on the post. Try wetting the o-ring at the top of the gas post before you try to connect the QD, then pull up the QD ring while pushing down on the top of the QD 'til it bottoms, then release the ring.

I did order a full set of poppets, but that wasn't the answer. Plus my vendor sent me some wonky ones with bent stands, one of which was completely disassembled. No matter, problem solved!
 
jwplessner said:
The trick was getting the QDs seated onto the post; they just weren't going on until I lifted up the QD ring, pushed the QD onto the post, and then released the ring. This is the case with every post, I'm not sure why.

Of course you had to do that with every post, that's how ball and sleeve connectors work. It's not a trick, it's just using the connectors. I'm a bit confused though, since it sounded like you were using ball lock QD's successfully on other kegs. Either way, I'm glad you figured it out and have everything working now.
 
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