Originally Posted by
Endopotential
I just went through the same headache myself. It was on the front exhaust, but rear stud which made for really tight quarters.
Anyone know what's on the backside or vicinity of the exhaust stud, if one should drill too deep or at an angle? Looks like there's a tunnel for the valve pushrod? It's still pretty far away from the combustion chamber or exhaust port, right?
...
I'm in Pacifica, in case you're nearby. Things I learned:
- I have a ton of Harbor Freight gear, and for the most part it's worked well and saved me a lot of money. But this is not where you want to skimp. The HF drill bits are not up to the task of drilling out heat hardened metal, and just dull out or snap.
- It's totally worth it to splurge $5 and get some decent cobalt drill bits. I got some Milwaukee Shockwave bits, and they cut through so much better
- Don't drill bigger than 9/32". That will still leave enough metal intact for you to run a tap through. If you drill the full 5/16" there won't be anything for your new stud to hang on to.
Good luck!