One of the beauties of these older, simpler, mechanical diesels is how simple the diagnostics can be. Especially for a no-start condition.
In a gasser, the fault can be either the fuel system, or the ignition system, ( assuming no mechanical problems). Either system can be controlled by a computer, many sensors and connections--a fault anywhere in the system can cause it not to run.
In our older diesels, its the fuel system, period. If the engine cranks at a high enough speed, the glow plugs light and fuel is present it will start. ( Glow plugs are not always required--I have started using a hair dryer blowing hot air into the air cleaner inlet). Don't start out thinking the injection pump is faulty, or has lost its timing. Do the simple stuff first. Make sure fuel flows, the filters are not clogged and the battery is fully charged. You can always remove a couple of injector lines at the injector end ( the metal ones) and see if they spritz a LITTLE fuel as the engine is cranked.
And keep us posted on your efforts to get it started!