Why won't my beer come out?!?

[Beerens]

I have been using kegs for over a year with no major problems. I went to get a pint of a beer that I have had carbing for a week. I attached my picnic hose and the keg made a strange noise (like a hissing grunt) for a second, beer only came out about 5 inches into the line and nothing would come out the end. I checked to see if it was under pressure and I purged the tank the the regulator kicked in and brought the pressure up to 10psi. My other keg is working fine. I took apart the black connector piece to see if I had somehow put it back together wrong, all was fine. Tried it again and same sound and nothing. I then pulled the picnic line off the keg that is working and put it onto the non-working one, nothing still. I then took the post off the side to see if I somehow forgot to put in the dip-tube thing or if the pop-it was installed incorrectly. All seemed fine. I was going to mess around with it more but decided to ask you humans for some help...

 

[Kahler]

Did you dry hop in this keg??

 

[Beerens]

No.

 

[Yooper]

Take off the post and hold the diptube (the long one) up to the light. If you can see through it, take apart the post itself. Remove the poppit and see if it has crud stuck in there.

When you tore it down the last time, how did the o-ring on that poppit look?

 

[Beerens]

I opened it up and the o-ring on the poppit looked ok. The diptube was clear. I was lost so I decided to just switch the out post and after I did that the sweet nectar flowed! It must have been the poppit. Thanks Kahler and Yooper!