IT WOULD BE HELPFUL TO HAVE A PHOTO OF THE CRACK, BUT THAT’S NOT POPSSIBLE FROM MY READING SO I’LL SHOOT IN THE DARK HERE. I HAVE SUCESSFULLY BRAZED CAST IRON, AND UNLESS THERE SOMETHING BEHIND THE CRACK TO CONTRAINDICATE SUCH AN APPROACH, THAT WOULD BE MY PREFERRED METHOD. YOU MAY END UP WITH BRAZING MATERIAL IN THE THREADS OF THE HOLE, BUT THAT COULD BE REMOVED WITH A TAP. IF IT WERE DONE CAREFULLY, YOU WOULD END UP WITH A LEAKPROOF PREMANENT REPAIR.
