Re: How fudged am I?
i know this goes without saying but be very careful in keeping shavings out of the engine when you drill them out. might be a good idea to use an aluminum cutting fluid when you tap the holes. probably impossible with the block in the frame but it wouldnt be a bad idea to use a drilling block to keep your drill 90 degrees to the block when your drilling them out. you really dont want to break a drill bit or tap off in there. youd be pretty fudged for sure then! so get some good sharp new bits n take your time or take it to an experienced metal shop if you think youd not be able to pull it off yourself. its not all that hard to do but you really just get the one chance n then your options dramatically get reduced if that doesnt turn out. if the broken bolt is close enough to the surface and has a small catch in it you can sometimes use a pointy tap or punch n hammer n lightly tap it to unscrew it. ive had success more than once with that method but it just depends on the situation. if you end up having to drill it out start with a small bit n get it started close to center as you can and work your way up a bit size at a time. if you get it nicely centered when you get all the way out to just shy of the original threads you can use a tap set the same size n pitch as the original bolt n probably clean the remaining bit of broken bolt out. use the cutting fluid n take your time. one turn in, half a turn out, repeat. you could get lucky n not need to helicoil that hole. ive heard f people just drilling them out n then tapping them the next size up as well but personally id use the helicoil route. if its done right its really better than before you started.
"love is the feeling you get when you like something as much as your motorcycle."-Hunter S. Thompson