Well I got screwed today, I was finishing up my 10.5 hotside, and was already putting on the downpipe well on of the bolts that screw the downpipe and O2 housing was not going in all the way, the other was good. we tried to unscrew that didn't work, it would unscrew but not all the way, tried to screw it again didn't work. So in the we tried everything to get the bolt out and it finally gave and broke. About 1/4 or 1/2 of the bolt is still in the thread.

Should I drill a hole in the bolt??
Any advice would help.

I just can't believe it would seize like that, because tied the bolt by hand first to make sure it went to the threat right. I am just hoping in didn't mess up the thread on the O2 housing.

 

take a small drill bit and drill into the bolt as straight as possible, then get a bolt extractor, lookes like a reverse cut drill bit kinda, and remove the remainder of the bolt. if it still doesnt want to come out, soak it in PB Blaster, you can get that at just about every parts house in america. be sure to run a tap thru the bolt hole to clean the threads up after you remove the broken bolt. and for future referance, if the bolt isnt all the way in and you have wrench it really hard to get it to turn, STOP!!!! you are probably cross threading it.

 

I understand what you saying, the problem was either we screwed the bolt it would get stuck, at one point it got frustrating screwing the bolt out and in without any success. At least we unscrewed a good portion of it out. But I just can't beleive it would seize like that. Well I am going to drill a hole through it after work today, we have already started doing that.