"One-way" fuel line valve..?

Any pump should push through the following pump, or pull through the upstream pump. I ran a REAR mounted NON energized pump on the street for years. ALL pumps have check valves. Whether or not they properly "check" is due to design, quality, dirt and debris, and wear

TWO things (or more) have changed since the old days. Quality of components, and the chemistry of the fuel. Alky gas evaporates, vapor locks, and boils more easily than the fuel we knew as kids