Similar crack in a Pontiac 6 cyl only it runs into a freeze plug hole. Sand blasted to grey iron, roughed up with 24 grit 1" each side of crack and sealed with Marine-Tex. Used expandable rubber plug in freeze plug hole. That was in 2010 and zero problem since.

[img]https://i.postimg.cc/348trwcL/40-Pontiac-engineand-trans-002.jpg[/img]


Evan