Flow issues / liquid disconnect not depressing poppet

[beet]

I've brewed a few K&K/bottled batches back in the day, and am getting back into homebrewing now. I'm towards the end of my first BIAB/kegging batch.

The issue that I'm seeing is that I can't get beer to flow out of the tap while the keg is pressurised. If I turn off the gas and purge the co2 from the keg, it flows (very slowly). After a while of turning the gas back on, it stops flowing again. If I manually depress the poppet on the liquid post at full pressure, beer spurts out as expected. No flow with hose + tap removed either.

This makes me think that the little rod inside the liquid disconnect isn't pushing down hard/far enough.

Brief explanation of the current setup:

* My beer is in a ball-lock cornelius keg, and has been for a day or so
* I finally got the gas connected without leaking this afternoon
* I'm using 5/8mm clear silicone tubing for both gas and liquid
* A cheap chinese MFL liquid disconnect (black) + swivel barb is on the "out" post, attached to a short length of tubing (~20cm) and a picnic tap
* A CO2 cylinder & regulator are connected via a cheap chinese MFL gas disconnect (white) + swivel barb on the "in" post
* Regulator is set to about 12 PSI
* The keg is pressurised (hisses when I pull up the pressure release valve), and there are no leaks that I can see by spraying soapy water.

When I bought the keg I also got a set of replacement seals + posts and poppets, but ended up using the old, second-hand posts + poppets, though I changed some of the grommets. The new posts/poppets were very hard to push down when screwed on to the keg, and I wasn't able to get gas into the tank with them fitted, which sounds like the same problem in different form.

My cheap chinese disconnects may be the issue. I'm tempted to replace the liquid one with one of the fancy stainless steel disconnects, but they're pricey enough that I want to be sure it'll fix the issue first.

It seems like the rod inside the disconnect may just need to be slightly longer so that it can push the poppet down further. I've considered adding a spacer or similar inside the liquid disconnect so that the rod sticks out further, but I'm not sure how well that will work.

Any suggestions for the best way to resolve this?

 

[Judanero]

My cheap chinese disconnects may be the issue.

Probably is, get a decent one (I'm not sure how good the stainless ones actually are) and you'll probably find the problem solved.

 

[Diesel80]

Did you put the posts on the wrong sides when reassembling?

Cheers,
D80

 

[mstrelan]

Keg lube might help. My first time using kegs I wasn't clicking the disconnect on hard enough. Lube makes that easier.

 

[droid]

all of the above....without lube here at the mo I squirt the post with star-san just to wet the o-ring, the disconnects are hard to get on when dry, when you disconnect the liquid post there should be some beer on the post and some should have entered the line when you put it on - tho with that short liquid line I have no experience

 

[stux]

Re disconnects,

There are two good brands

CMB and Cornelius

The CMB ones say CMB on them, have a plastic pin and a flat top. Made in Germany and your Chinese ones are probably a bad rip off of them.

And the Cornelius ones, they have a domed top, are even better, have a metal pin, and just seem to work better, with a nicer fit. They both break down for cleaning too. But the Cornelius breaks into more parts.

I do not have experience with the all metal disconnects,

If buying plastic, definitely go for the Cornelius ones if you can help it, but some online stores will show the Cornelius ones in their picture, and ship the CMB ones

CMB clones I have had have rusted, or lost their plating while in starsan/PBW!

 

[beet]

Wow. Okay. I completely missed the collar as a moving part of the disconnects. It lifts up, the disconnect goes on slightly further than before (without any effort), and beer comes out super fast. Excellent. Thanks for the suggestions guys.