What is this case hole?

[The Watson]

See yellow arrow below.....This hole was not being used when I tore apart my engine. Is this the location that should have a bolt and nut (with 2 washers)? If so, anyone know the bolt sizing, etc? Wondering why also.

[Amstaff]

yes, that is the location with the bolt. I will have to check the size.

[KTL]

Yes there is a M8 bolt and lock nut that goes thru the case there. Reason for the bolt is because of the oil gallery location that is just above and to the right of the subject bolt hole. That bolt helps ensure a good seal for that oil gallery. Bolt length is typically 45mm or 55mm long

That oil gallery is a very important one. It's the one that feeds the entire engine, like the trunk of a tree feeds all the branches.

[The Watson]

Great - thanks guys.