Nobody mentioned this, but you want to position the breaker bar a few inches above the frame so the starter can develop some torque before the bar comes into contact with the frame. I use a piece of 2x4 to protect the frame. Also, I think a ratchet works better than a breaker bar for the starter bump. The breaker bar handle will not stay exactly straight when it hits, losing some effectiveness. The ratchet handle will stay straight. I would put some heat right on the head of the bolt, not the crank, and then hit it with the starter bump.

