Doing diesel purge - "ran out of fuel"

[mikeyfev1]

I was doing my first diesel purge today on my 1985 300D KaliKar. I setup everything the way I thought it should be, started the car. All fine. Watched the return flow for a minutes, was pumping as it should. Pickup line deep inside the fluid - total of 1 liter in bottle.

Went for a short drive. Got about 3 miles away and I got "out of fuel" symptoms. Managed to get to my daughter's house, raised the hood and looked at my purge tank (engine was still running, but poorly). No return fuel coming out of the return line. No fuel in the primary filter! Engine dies.

So I started pumping the primer and after many minutes of this, still no fuel in primary filter. Can easily blow though primary filter and fuel line from filter into bottom of purge tank. About 1/2 liter of purge fuel remaining. Pickup line did not leave the bottom of the purge tank, the purge tank was held in place and did not go inverted.

Above and beyond "why did the engine stop fuel pickup" is why can't I prime the lines? What should I be looking for? I need to solve this problem first.