Got to the bottom of it !!
What they didn`t say when fitting the higher pressure pump,was that as it`s higher pressure than the standard 120 psi,you have to adjust the pressure relief valve to compensate,it`s like a double lock nut with a dome on one end,it`s where the sol hose joins,this needs to be screwed out,when it starts pulsing that is when it`s doing damage,Woodbridge fixed the pump for me,so must have just blown out a seal or something.
Have left them both the spares i had,so they can make 1 decent spare,i hope