On my N55 I was doing my belt/pulleys/tensioner and replacing my oil cooler gasket and oil filter housing gasket and ran into a couple of problems with the oil filter housing gasket.
First, the bolt that's underneath (that everyone complains about) would not turn, despite oiling it, waiting, and heating it (and I was using the correct e-12 socket). When I saw that the head was starting to get a twist in it I decided not to push my luck and skip the oil filter housing gasket for now.
I set my torque wrench to the spec 16nm and tightened up the bolt under the intake manifold, and then started on the final bolt on the top. Unfortunately, it snapped partway down, so the bottom part of the bolt is threaded into the engine block. The break is about 1cm below the surface of the hole.
This is the location of the bolt that broke:
So, will a left-thread screw/bolt extractor kit like this be my best bet? Something like this?
I assume that I would need a good bit to drill into the bolt, then use one of the extractor bits to bite in and reverse it out. I don't have an impact wrench, so it would be a combination of regular power drill or hand tools.
Any other suggestions?