is it possible to close off the fuel return line and build pressure on the 2002 7.3
thanks joseph

 

I wouldn't dead head the pump.
You could install a low cost regulator kit to increase fuel pressure or try a spring shim. Also, the fuel heater helps in cold temps for jelling as heated fuel is circulated throughout the system. Not to mention continuous filtering. Return to tank is nice during filter changes or should the tank run empty. Much easier to purge the air. Dead heading the pump could damage it.. If fuel delivery/pressure is suspect, easy to check.