oil leak?

hi there i,m having trouble with oil leaking from my k&n induction kit on my j-plate fiesta xr2i 8v it seems as though the oil from the rocker cover is coming back through the breather filter and dripping out my k&n i have done an engine flush but still have same problem and fitted a new breather filter but no joy i have been told it may be the oil pump that is nackered any suggestions would be most welcome.

cheers stu