OK, I finally got the correct reducer and was able to plumb the ‘short circuit’ that would let me run the fuel pump and start looking for leaks. I had a pretty big leak at the bottom of the tank, but I chose not to use any sealant for the temporary connection, so I’m expecting that.
Short Circuit of Fuel Supply to Fuel Return Line
What I didn’t expect is no flow at all through the circuit. Nothing. Nada. Zippo. Ничего. Nothing in the gascolator, no dribble or drainage from the fuel return line at the filler neck in the tank. Aha! Open the fuel cut-off valve! Still nothing. Wait, there’s something—a leak from the input port of the Red Cube fuel flow transducer. I shut things down and cleaned up the mess. When I get back from vacation, I’ll pull the red cube and see if I did something stupid like leave a protective cap inside.