Fuel pump check valve

[the_weirdo]

I have a question about the fuel pump check valve. I got a tank full of mud over the weekend (it was a VERY deep puddle) and it clogged my fuel filters so bad that the fuel pump stopped pumping gas. I have cleaned it all out and replaced the filters.

On to the question: I want to make sure that everything is clean before I put it back together. In the picture below the red box is the fuel line outlet, the purple box is the fuel pump connection, and the blue box is a pressure regulator/filter. When I blow throw the fuel pump connection with my mouth, I get very little air out of the pressure regulator and fuel line connection. I assume that it is because the required pressure for the regulator is much higher than my mouth's PSI.

Can someone confirm that I should not be able to blow freely throw the pressure regulator? I just want to make sure that it is not blocked with tons of mud and that it is operating normally.

[the_weirdo]

Update for anyone who is searching. The fuel pump regulator has a spring and diaphragm in it. You should not get much air out of the fuel outlet when you blow into the fuel inlet. Completely normal.