I believe he is meaning the return connection bolt thingie; it is the only screen gizmo anywhere about the pump.

 

Jim, Iwould also check the idle screw locknut and be sure it's still tight since you adjusted it. Also you said you checked the linkage real good for binding? Other than that I don't know if the ksb would do this or not. Also check your connection on the fuel solenoid. Hope this helps! sure is cheaper than a fuel inj. pump!!!