Hello, I hope the following is of assistance.
First check that the immobiliser LED behaves as it should, turn the ignition on the LED should be on for 3 seconds then off, if it flashes then the immobiliser is stopping the van starting.
If this is OK make sure the pump timing is correct (on TDDi) the pin should fit in the pump and the chain should be tight between the pump and crank.
This engine is a pain to bleed when the pump has been changed, the best way to bleed it is to fit an inline priming pump between the fuel filter and fuel pump, remove the fuel pipe that comes from the filter and fit the priming pump to the connector, pump the primer until fuel comes from it then connect the pipe to the fuel injection pump to the primer so the primer is inline, crack off the injector pipes and pump the primer until fuel comes from a pipe, tighten the injectors then get an assistant to crank the engine while pumping the priming pump, this should allow the engine to start if the non start is due to air. Once the engine is running allow it to idle for a few minutes then remove the priming pump. An example of the type of priming pump you need is
It is possible there is another fault causing the non start, it depends on why the pump was replaced to start with, if it was replaced for a non start issue then I would try a diagnostic scan to obtain any PCM fault codes.
I hope this helps but if you have more questions regarding this let me know and I'll reply as soon as I'm able to.