The inj pump is just that.. a pump..
It has pistons, plungers and springs inside.. so yes.. u can have fuel going in, and fuel coming out and nothing else, if the pistons, plungers and springs are stuck.
This is my area of knowledge.. I was gonna say expertise but…
Anyway, remove all the fittings off the top cover.. ALL OF THEM.
If done correctly, u should be looking at an open hole in the cover… now loosen as many steel lines AT THE INJECTORS as u can get to, just a turn or 2.. enough to let any trapped air out..
Pull the throttle to wide open and give’r a spin..
DONT burn up the starter.. a couple of 7 second count on the starter will tell u if your pump is pumping..(injectors are dripping)
If that doesn’t work.. remove the top cover..(3 screws & washers)..
Do a Google search on Stanadyne metering valve to get an idea of what your looking for/at..
MAKE SURE ITS FREE.. REAL FREE.. u should be able to flick it with your finger and it return on it’s own..
How about the QUALITY AND QUANTITY OF FUEL your trying to start it on.?? U could bypass the tank.. just put a rubber hose on the supply pump where it would “normally” suck from the tank and get a 5 gallon container of fresh diesel fuel..& put ur hose in it..
Be careful taking the screws outta the top cover.. don’t put to much force on them cuz they will snap..
Good luck and feel free to reach out in a prvt msg if need be..