ford transit 2.4 turbo diesel rear drive non start?

ford transit 2006 2.4 turbo diesel is cranking but not firing up. There is diesel in the tank but no diesel is coming through the injector pipes. We had a second hand engine together with injector pump and injectors fitted to the van but still its not starting.Someone came and said he coded the pump but i am still wondering why i cant see any diesel coming out of the injector pipe ( when cranking) which i disconnected from the injector