B2600i Cracked Block?

I did a post about what I thought was a bad freeze plug. Well I think it might be a hair line crack in the block. On the back side of the water pump there is a tube formed in the cast of the block. The side of this tube was damp with coolant. If there is a crack it is so small that is only seeps very slowly but enough to run down to and past the freeze plug. According to coolant flow diagrams coolant flows from the water pump through this tube into the block. I cleaned the area with fine sandpaper and then steel wool. Then I spread a coating of Epoxysteel over the area in question. I did this several days ago and I THINK it might be fixed. Just wondering if anyone ever experienced a problem in this area of the block?