Truck Repair: ford f 700 diesel truck, diesel truck, f 700

Question
have older model ford f 700 diesel truck less than 50'000 miles has been runnig great lost fuel from first fuel filter have replaced filter now were not getting any fuel to cylinders can make it run on either but no fuel yet. help  p s have lots of shade tree  mech knowledge but not much with diesel thanks

Answer
Open the lines on the cylinders one by one while cranking the engine --- the fuel system has air trapped in it --- you are attempting to bleed each injector line one by one --- when fuel reaches the open line - close it and move on to the next cylinder,