Leaking from the beer side

one of my used corny kegs has a very slight leak from the beer side. its under pressure, and the leak is slow enough that it took days to be noticed.

in an effort to trouble-shoot in order of most likely to least likely, what should I look at first?

the little poppet valve inside the post?
the black disconnect?

I put all new o-rings on this, so its possible I didn't get it tight enough when I put the post back on.

The beer line from the black disconnect seems to be tight too, so its gotta be in the disconnect, or the keg itself.

(and I don't own keg lube, yet)

Get some soapy water around those connections and the bubbles will tell the tale.

The poppets shouldn't be the problem if it's leaking while connected. Did you try some keg lube on the post o-rings?

I also make a habit of wrapping teflon tape around all of the post threads before reconnecting the posts.

Found it!
It was the beer line to the picnic tap. the other two I wrapped in teflon tape where the barb fitting connects to the beer disconnect. This one, I didn't and that's where it was bubbling from.

Wrapped it up tight. Now I'm just afraid I've wasted a lot of CO2 since I've been carbing the keg this week. Oh well, small price to pay. There was maybe 2-3 tablespoons of beer in the bottom. Not bad considering what could've been...

Thanks!

Wait. Where did you wrap teflon tape? On the flare fittings? You're not supposed to use tape on flare or compression fittings.

uh.... am I missing something? The beer side should leak beer not CO2

Yes, its like a compression fitting. 2 pieces, barb on one end that is then flared on the other side. that slides through the compression nut, then you slip the hose on, then the nut screws down onto the actual black disconnect.
its the threads on the disconnect i put two wraps of tape on.

I know I read that as a suggestion somewhere and did it on my other two disconnects as well as the one for my little CO2 dispenser thing.

it was screwed down as tight as possible and still leaked...over night with the tape, no leaks.

Why is it not a good idea to use the tape??

I'm speaking on behalf of general plumbing connection wisdom of course. You found that it worked for you so that's good. Flare and Compression fittings do not rely on the threads for sealing. If you stop the leak at the threads, you just encourage the leak to find its way to the joint between the tube/nut. The nut is there to simply apply sealing pressure between the fitting and the tubing.

I've seen that most leaks on these types of fittings are due to overtightning. You end up deforming the O-ring or ferrules.

that makes sense. i'll keep an eye on it for new leaking. maybe the fact that I pulled it apart and reconnected it got it correctly sealed this time and the thread tape plays no real part in it.