Yesterday, I finished removing a broken off bolt on the top of number five cylinder. It was broken off flush to the cylinder head and had been that way for a long time before I got the car. Drilling a pilot hole is tough so this is what I used. I have a Dremel tool with an angle head attachment. I used this bit from Dremel to hog out the bolt and save the threads in the cylinder head.

9906 Tungsten Carbide Cutter / Model: 9906


This engine has never been apart and all the bolts are original with the tabs bent over the bolt heads. I also soaked all the bolts with PB Blaster for a week. The others all came out with a 9/16 end wrench, and/or breaker bar and socket (Snap-on) I recommend a high quality six point end wrench if possible but a 12 point will work. If using a breaker bar and socket, try a 3/8" size breaker bar first. The 1/2'' breaker bar is too powerful and doesn't give you the "feel" before twisting the bolt. I started by tightening the bolt first and the loosening in very small increments until it started to move. Then loosening maybe a 1/4 turn and back again until it loosens enough to thread all the way out. Low end hand wrenches are trouble when it comes to this job. Use Craftsman or better for the best luck as cheapo wrenches/sockets will be your worst enemy in this. Sears used to or still does make a lower grade of hand tools, branded as Sears, make sure it is a Craftsman wrench.Take your time with the Dremel bit for a broken a bolt being careful to not damage the threads in the head. Worse case scenario if the threads are ruined and I have seen people do this on all the upper row of manifold bolt holes. They hog out the threads and install grade 8 bolts and nuts on the up side to tighten the manifold. This does mean a small amount of grinding the upper head side area around some the holes so the nut and washer can sit flat. Again, the Dremel is good for this job as well. Hope this helps some.

Mark