Thanks for the info, i managed to find some other volvo 5 cylinder upper block pics and looks like there is bolt hole just behind it, is it only for bolt or does it also work as oil gallery? It is surprisingly thin wall just at that point

Any info about B5252S block thickness behind rear main seal or is there some kind of plate? So my problem is that i was attempting to remove leaking rear main seal with screw trick from B5252S engine, but thing was really stuck so i screwed through it. I though that what if screw goes through someth...