Filament pinched too tight against the drive gear

[mediathread]

I have been trying to test my extruder based on the video. When i ask it to extrude any amount of filament, nothing happens .. If I push down on the head plastic arm just a little, i can see the motor moving and some plastic comes out.

Is there an adjustment for this? I have tried to tighten the screw while i have tension on the spring, but that didn't help..

I am sure its something simple and stupid.

Thanks in advance for any help.