Hi,
The breaded modification is done. Thanks to you all for your support, this site help a lot that everyone shares his knowledgeNow let’s hope there is no oil anymore going down in the engine, or AirBox.
As expected, all oil was already in the engine and nothing in the oil tank anymore. The oil pump has indeed some virtual leak looking at the used/made tolerances in the oil pump.
The previous owner modified the rocker cover by placing a metal shielding plate in front of the banjo bold. Indeed this prevents the oil going down to the AirBox but also limits the breading capacity by blocking the venting tube. This is solved now also, and is not healthy for the engine I guess.
I modified the rocker cover by riviting aluminum plugs into it to close the M14 holes. The material color is a bit different due to to fact I didn’t have casted material.