[supereal]

The photo shows orange gunk. That is almost always a sign that water entered the engine some time. The front shows evidence of the same. If it was stored in the open, it could happen. Otherwise, there may be cracks in the block that allowed water in the jackets to flow into the pan.. Look at the inside walls of the lower end for holes or cracks. that is the usual place for freeze cracks. We have seen too many like that to believe that block is worth rebuilding.