I attempted to drill out a bolt that I had snapped the head off of(Due to a shop using air tools, and cross threading it when tightening it in the past). I drilled off of the bolt, and kinda made my own path, but it went down into where the coolant flows. It is a bolt holding down the Thermostat housing. My question is, Is there so much pressure that I couldnt just tap the hole I made and put a new bolt in it, or do I have to replace the whole intake? My other question is what PART IS IT?!?!?! I have attempted to search and search but cant seem to figure it out. It is what the thermostat sits in, that has two bolt threads on either side of the thermostat. My research makes me think it is an intake manifold? But I cant find one to buy that is what Mine is. My vehicle is a 2wd 2001 Mazda B3000. I'm really hoping I can just tap the new hole I made and put a bolt in it, I don't use this vehicle as a daily driver anymore, will just be used for truck stuff when needed. Any help would be much appreciated. Thanks In Advance.

 

Photo?

 

Photo helps. If drilling/extractor doesn't remove it, I think drilling and tapping and using a new bolt or stud is a good idea.

I might recommend installing a stud there and then a nut to hold it, this is not where you want to keep "testing" your newly-cut threads. And use a good sealant like Loctite red to seal the stud at the engine end.