Topic: broken bolt problems!!!

[chainsaw]

During disassembly I broke off a couple bolts that were frozen in the head. I have been using the bolt extractor kit to get them all out, but these are not budging. I drilled straight through them and tried to extract them and nothing. I have 3 just like the one in the photo to get out and I feel like I'm running out of options before I start damaging the head. Anyone have any tips?

[Markcb750]

I had to drill out and put in Helicoil inserts.  Work hard at drilling parallel to the existing center line. 


Which reminds me, why are metric Helicoils more then twice as expensive as SAE?

[fastbroshi]

Whatever that is, I don't think it's a screw or bolt, looks like a dowel.  Have you tried any penetrating oil?  You'll hear a bunch of recommendations like ATF, regular motor oil, wd40, and other lubricants, they all seem to work pretty good.  Be careful, don't overdo it with that EZ out.  Those are made of a VERY hard steel and you won't be drilling through it if you snap it.