pity, been leaking a while if emulsified, or recently gone in a bigger fashion perhaps
I can't say it's a reason to got to a rebuild although these things can show us more when apart
just done one which revealed why the gasket would have gone, finding the block had already been sleeved and one had slightly dropped, unloading a few mm from the fire ring of the gasket, reassembled and runs well enough, only back together due to the new cost scenario and is a deferred rebuild for sure, just mobile right now
although I really would urge you to consider authorising at least an exhaust valve re-lap at the time, they won't be good
in fact doing that on the car I mention also revealed something had previously been trapped between exhaust valve 6 and its seat, in considerable danger of blowing out that valve in the short term due to blow by/hot spot, we'd not have known had I not pushed for permission to go ahead, again it will form part of the deferred rebuild in terms of re-cutting the seat/s but it cleaned up enough to seat better for now
the majority are straightforward enough, some have some block corrosion which would be better removed by decking but that's prohibitive for most
