Thanks for all the suggestions. Another idea I had was that maybe the oil filters (both frams with the black grip) are causing it after all. Maybe when I screw it down, the stud it goes on is going to deep and hitting the filter bypass valve. That would certainly make it run great but not filter at all. But yes I think I will see what I can find for oil treatment and I sure hope it isn't an oil pump. All my tools are back in the states.
Many thanks guys,
Matt