Got it. My fix is an inline " looks like a fuel filter " universal fuel pump wired to turn on as soon as the glow plugs are in operation, it also runs with the key in the run position. I've got a 3 cyl Kubota on a ride on sweeper that had intermittent long crank, now it is a glow and instant start.

I put these pumps get put on other small to medium industrial diesels as primary lift pumps. If I had an old decrepit on the road diesel I'd do the same.