Hello guys I think I need some advice.
I took apart the crank box 'cause its aluminum cast had fractured. replaced it and re-asembled all the rocker arms exactly in the position they were installed before. Actually the system is engineered 'simple-stupid' 'cause you need to be really good to make a mistake. In fact the shaft on which the rocker arms are installed has 3 notches which lodge the 3 ball-screws which bolt down the box in place. So the shaft cannot be improperly rotated or positioned. Assemblying the other components is a forced-way job meaning that you cannot divert from the right path.
That said I re-assebled everything and adjusted the valve lash by the book and did a short (5' ) first run without the crank box lid in order to make sure the rocker arms were properly lubricated.
Starting from the end of the shaft were the oil is pumped in i could see the rocker arms # 2, 3, 4, 5, 6 properly lubricated with oil dripping from the top pinhole and being channeled toward the valve cap.
Only the rocker #1 (the closest to the oil inlet) was lubricated 'cause I could see the oil flowing out from the sides but no oil was coming up from the top pin-hole. Engine cold and pressure readings 2.5 bar.
It goes without saying I made sure the hollow shaft was clean as well as all the pinholes on it and on the arms.
Do you have any possible explanation? it stands to reason that the oil pressure is higher on that side and that oil ought to come out there rather than the following rockers.
I plan on running more extensively to see if anything changes but it is really puzzling.