Broke my water pump bolt. Now what? (Update - broken bolt is out)

volaredon said
No that will actually get him an oversized hole .
When you drill and tap a hole the drill size for the tap is smaller than the listed thread size.
As far as the vise grip truck, if he's EASY with them so he don't mess up what's there he might just be able to walk what's left outta there especially if the reason for the bolt breaking was corrosion to the water pump which is now not there it may be pretty free in the block
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He's suggesting using the water pump as a template to center the hole.
The actual drilling of the bolt must under size.
I've drilled out bolts several times. The bit has to be smaller than the threads and then some.
Using a bit made for hard steel helps, and the left hand thread bits are good for this job - there are some made specificlly for this and in my experience work OK.