Thank you for the responce. Yes I read up on bump starting and I have written a warning in the cabin for everyone else to see.
I did put my industrial mains jump pack on and it did struggle to start due to the air. Also cracked off the 10mm bleeders.
There was air in the system. Took off the filter, filled more diesel, took off the intake pipe and squirted some easy start untill it fired (not reccomended i know)
Held the revs to 2000 rpm and all is good.
Now starts on the first turn of the key. My previous filter was a pattern one (previous owner) and took 2-3 attempts to start.