The bane of my existence for a while now has been this stupid fucking broken bolt:
I tried everything to get it out. Vice grips, of course, didn't work.* Heat, PB Blaster, more heat and vice grips still didn't work. I tried brazing a nut onto the end of the bolt. I twisted the nut right off w/ little effort. Then I MIG welded a nut on the end. When I turned that, the bolt just twisted off below the weld.
I decided I'd have to bite the proverbial bullet and pull the head and drill the bolt out. I had very little confidence that I could do this without destroying the head. But its no use to me just sitting there w/ a broken bolt in it either, so here goes.
SMILE! This will be fun! ermm...
Ground the bolt flat and dimpled it:
Started drilling:
Bigger:
Got to the proper-ish size and pulled out the taps. As you could probably guess, Harbor Freight taps are pretty much garbage. Well, at least for anything more than a single use. Here's the tap I used next to an unused tap:
I'm so lucky that didn't snap off inside the bolt hole!
So, I did a pretty good job of buggering up the bolt hole, but amazingly it seems to have worked. The intake bolts up in the proper manner:
So then, after feeling proud of myself for about half a second, I looked over the rest of the head. That's when I noticed the cam journals. These wear patterns are worrisome. I've not been inside too many engines, so I don't know if this wear is catastrophic or if I should just polish them up and move along.
So, after all that, this head may be trash. I'm off to go seek the advice of the moto elders....
*
"VISE-GRIPS: Generally used after pliers to further round
off bolt heads. If nothing else is available, they can also be used to
transfer intense welding heat to the palm of your hand."