Does it matter how you hook up the injector return lines?
Are the two hose barbs directional?
No matter which barb I cap off, it leaks. I changed the cap and the lines on all the injectors.
Not directional. Is there possibly a blockage somewhere on the pump? Normally #1 gets a cap and #4 goes to the pump, but it shouldn't matter.
If I take off the line from the injector back to the pump and blow into it, should I be able to drive the fuel back to the filter?
No clue as I've never tried it. I would think it should go to the return line if anything. I don't see anything in my pump book either that says what path the returned fuel takes.