I always start an extraction with a left-handed cobalt drill bit.
Sometimes it extracts the broke off bolt while you're drilling the pilot hole.
All of my LH drill bits came in Matco or Snap-on kits. $$$
So much other stuff is available now at much friendlier prices.
Here's a rather complete set at Walmart.
All of my kits only came with 5 sizes...

Cobalt Left Hand Drill Bit Set, 13Pcs, 1/16-1/4" with TiN Coating - Walmart.com

 

Thank you so much guys. I removed the turbo intercooler piping, AC compressor, AC bracket, and radiator. I tied the air compressor to my swaybar, which i also loosened.

I’ve been drilling away all Sunday since 8am this morning. I don’t think I’ve gotten the bolt out yet. A depth check leads me to believe i am all the way at the back of the bolt hole, but trying to thread my bolt inside leads to spinning and no catch.

i’ve either destroyed the threads, or done something else entirely, unless i need to keep drilling until i see dark iron? Or something?

 

I


just needed another 5 minutes! Broke through! Then drilled some more, and now I’m left with this horrifying mess. I think she’s done for. I have no idea how to fix this.

 

A bit hard to see what's happening there, have you tried removing the remnants with an extractor? Looks like it should just be a pretty thin, hollowed-out core left in there.

 

i ultimately drilled out the entire hole to puncture out the backside through the iron block. The goal was to put a long M8 bolt (M8 1.25x90 or x100) and tighten a washered nut to the back, and tighten. Unfortunately there was no spin space for the nut, unless i continue drilling out along the side of the engine block. I think that’s a bad idea, to thin the walls of the engine as i push boost.

I will now tap the hole to accept an M10 thread, and hope that a new M10 bolt in the stock size (1.25x75mm shank) will hold the pump to the block at the appropriate torque. Fingers crossed.

 

Oh ok, but if you can remove the remnants of the broken bolt, the threads in the block should be fine, no?

 

Unfortunately no. I completely erased all essence of threading inside the iron end of the bolt hole. It’s all smooth-bore now.

During my drilling to get an extractor on the broken-off bolt from previous, the chips and bolt pieces completely failed to extract, and I was unable to pull any pieces or extract to keep the threads intact. Better to just make new threads than possibly crossthread a new bolt.