Slow keg leak

I have a slow leak in my keg (only have one keg right now or this would be easier to test) and I was just wondering if anyone has experienced this before I start buying multiple new parts.

The leak is on the beverage out side, and only occurs when I attach my quick disconnect and tubing. Ball lock, if it matters. When the disconnect is hooked up, if I leave it alone for a couple hours a small but noticeable amount of beer and foam has leaked out the bottom of the disconnect. It's definitely on as tightly as it can be. Any thoughts on whether it's the disconnect or one of the keg pieces? I'm leaning toward the disconnect just because when it's not attached the keg has zero leakage.

I discovered this the hard way when I went away for a week and came back to find 3 gallons of brown ale covering the floor of my kegerator

that's depressing is the liquid seeping out from underneath the disconnect or from the hose attached to the disconnect?

Is the post tight? Like you tightened it with a wrench? Did you use keg lube? Is it a brand new disconnect? If it's a used one take it apart and clean it.

like akthor said, taking it apart and cleaning it might help. i'm thinking this is the problem

Thanks for the advice all, I will try to take it apart and clean. The disconnect is new to me but bought lightly used off Craigslist, came with the keg. I did my best to run some PBW and Star San through the whole shebang before using it. The leak is definitely out the bottom of the disconnect, not out of the top/hose.

I did tighten the post with a wrench, but I've never heard of keg lube.

Did you try a different disconnect to try to isolate the problem? Even new ones are bad every now and again. I've read about guys driving themselves nuts assuming the QD was in good shape only to find out later that this was a problem.

You can also try replacing the O Ring and using keg lube. The lube just keeps the oring from rolling when you slide the disconnect on. No keg lube? A small dab of vasleine will also work in a pinch, but it will degrade rubber orings (black ones) if used constantly. Silicone (usually red) are a great replacement.

Yes, the QD.
FYI: Out of the 360,000+ kegs we've gone through of the years, one post defect we have seen (if a post is bad; not the poppet) is that there tends to be a crack in the metal under the post O-ring. This is where the s/s is thinist. Doesn't make sense but if a post is bad we look first of bubbles underneath the O-ring.

Matt