water glass
 

some of you might know this process of sealing, someone mentioned it to me, I have yet to know it's application, but it was used to preserve eggs. eggs?

Re: water glass
 

your right about the eggs, but is is also used to seal cracks in blocks and radiators, that stuff works, its sold in parts stores like kragens, it has copper added to really seal cracks, ive sealed cracks in flatheads that you could put the edge of a pocket knife in, BUT and i repeat BUT follow the directions to the letter, water glass (sodium silica or silicate) seals by using heat an exposure to air, if the cores in the rad are not covered with water when using this they will start to plug, the only product on the market that will do what it says it will do, follow the direction and you will have an almost permante repair

Re: water glass
 

thanks,
the head is off the block, i do have another head that i am soaking in diesel for now while i break down the block, the the crack on the surface of the block is from the water jacket inlet at the center of the block on the surface, heading toward the number one center head-stud hole , i see this stud has only about 5/8" to grab and i'd like to prevent a further issue when torquing . i understand there are other options to prevent furthering the crack, a very thin short crack in a venerable location.
no plan to weld this. being cast what might be a better option ?