If it's where you can lock the head up in a drill press, why don't you
find the center of the bolt and step drill it till you get it close
enough to the inside thread diameter to chase it out with a tap. You'll
need a bottoming tap too unless the hole is a good bit deeper than the
bolt.

That heat deal doesn't work so well with aluminum and steel. Once I had
the same thing happen to a 911 head, and ended up having another bolt
welded onto the exposed threads of the broken one. but if I had it to
do again I'd drill it out.

Jim

On Jun 29, 2004, at 8:58 PM, Jonce Fancher wrote:

> Hi all
> im in the process of removing the swiss cheese exhaust system from my
> 84 7 passanger van with only 20 k miles. so after using a chisle and
> center punch to cu the nuts off of 2 studs and thinking im golden the
> last bolt after soaking for 2 weeks in PB blast snapped off2 threads
> exposed from the head. so now i have a forzen partial bolt in the head
> of the # 1 cylinder upper. the question is what should i do to remove
> it?? Mig something to it and beat on it with the heat from migging and
> the extra grip that i added i just turn it out right?? what ive done is
> wire brushed it to remove all corrosion and dirt then soaked with more
> PB Blast waiting for me to come up with a grand idea to remove it. any
> suggestions?  or FAQ pages? thanks Jonce
>