<VV> Broken bolt in crank...

[Bill Elliott]

Always go with your first instinct... as I was mounting the flywheel on 
the engine I'm assembling, one of those special 11/32 bolts didn't seem 
to want to go in right. I normally chase all threads when assembling, 
but I didn't have one of the unusual size taps. The threads on both hole 
and bolt looked okay and on like the third try it seemed to go in easier 
(but still a bit tight for my comfort). I should have stopped at that 
point... but I didn't.

As I was torquing down the bolts, the head on this one popped off. Now 
that I have disassembled everything again and examined the situation 
more closely, it appears that the bolt is slightly cross-threaded in the 
crank AND shows evidence of having been "attacked" by an impact tool 
sometime in it's history...

Now in 20 years of working on Corvairs I've never seen this problem 
before. I do have almost 1/4" of the broken bolt protruding, but it is 
in _tight_.

Any advice on how to best extract it without damaging my crank?

Also, assuming that I have permanently damaged the threads (I did just 
find and order the correct tap) what is anyone's experience in drilling 
and retapping to 3/8-24?

It's bad enough when major problems happen, but it's even worse when 
they were clearly preventable with a bit more care...

Thanks!
Bill


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