How do you prime engine on 1999 gmc diesel 2500 van?

To prime the engine on a 1999 GMC Diesel 2500 van, first ensure that the fuel tank is sufficiently filled. Locate the fuel filter and remove the air bleeder screw, then turn the ignition key to the "on" position without starting the engine to allow the fuel pump to run. Once fuel begins to seep from the bleeder screw, close it securely. Finally, try starting the engine; it may take a few attempts if it had run out of fuel completely.