Water separator won't drain after new filter

[ZeroOne]

Took the truck to the dealer for its first fuel filter(s) change at 10k-mi, about a month ago. This is the first time since the new filters that I've tried to drain the water separator. I've done it a few times before and know I'm doing it right, but for some reason NOTHING comes out. Only ONE drip and thats it. Nothing else whatsoever. Not a slow drip, not a trickle, nothing. It doesn't matter if its just been run, sat all night, or ignition turned to on (not started) and back off. I've been going to the same fuel stops for the life of the truck. Doubt there is any clogging on a brand new filter with the usual stations. Anyone ever heard of this before? It's really annoying when the easiest things find ways to become difficult.

[CMB430]

The simple side of me says that the hole in the housing that exists to support the yellow plastic valve is clogged. Though it may cost you $71 from Ford for a new set, open the lower filter and remove it. Perhaps the oil changer at the dealer that did the work had greasy hands or something. I will be changing mine out in Dec, and hope I don't have the same issue. If you can not see inside, try one of those 'one man bleeders' from Napa. Open the valve and see if you can suck fluid out. If that fails, back to the que at Ford.

[Samuel1941]

As I recall there have been some instances of some o-ring on the old filter not coming out when the filter was changed and causing a problem.

Obviously something is wrong and I'd sure want to open the housing and insure the filter is properly installed, that it is the correct filter, and that nothing is inside the filter housing that shouldn't be.