Coolant leak -hydro locked engine

Not sure, but I do know the regular JB Weld isn't for use around gas. We sell a product at work I was lookin at tonight called SteelStick that's a 2 part epoxy putty that you open and knead together. Says you can machine it and even thread it when cured and it also says you can use it around fuel. It sorta reminds me of the 2 part putty that you repair gas tanks with.