Guys who supplied the used engine have supplied and fitted a replacment. Hot start problem is solved. Pump and injectors were changed with the engine. Unfortunatly no one has time to do an autopsy on the old engine.

My feeling is that Dave was on the right lines with this, either pump failing to build presure fast enough or injectors not holding it. As the engine would fight the starter on first hot crank I suspect the latter. Could this have been the cause of mechanical failure?