I suspect it might be sucking some from the threads on the inner valley bolts. Like Chip suggested Im gonna use some thread sealer in there....
Im also gonna use some penetrating locktite sealer on the pushrod sleeves.
and when the heads are out check vave guide clearance and valve seals...
Another thing to check is crankcase ventilation,if it's not vented enough or has high crankcase pressure, the crankcase pressure along with cylinder draw can push and pull oil into intakes,bolt threads and other areas that wouldn't normally see oil.
