[DeTomaso] Motor Mount Bolts Sheered Off

[Michael Becker]

Both of the bolts attaching the motor mount to the block on the driver's
side were sheered off on my car.  I'm not sure how long it's been like that,
but this would seem to explain some vibrations I have been feeling during
acceleration.  I removed the bolts holding the motor mounts to the frame and
jacked up the engine a bit.  The first bolt was easily extracted using an
easy out.  The second bold has proven to be almost impossible.  I ended up
drilling several holes in the stuck bolt and finally it came out in many
pieces and lots of metal dust.  Unfortunately, it appears as though many of
the threads somehow cracked off the bolt and they seem to be lodged within
the threads of the block!  It's almost as if the bolt threads are fused to
the block.  I'm beginning to think that the bolt had been cross-threaded
last time it was installed, causing the threads to weaken and crack upon
forced extraction.

Now I don't know what to do.  I can't re-cut the theads because it looks
impossible to get the tap (or is it the die) in the mangled/obstructed hole.
I could possibly drill it out and tap with a larger size.  The current size
is 7/16 x 14.  I'm not sure how much bigger I could make the hole without
compromising the block.

Any suggestions?

Thanks,
Mike Becker
(619) 804-3757