I cranked up the 750 today and heard a grinding noise. I presume the starter got hung up. I did it one more time, and it started (after a grinding noise). I drove it home and decided not to try it anymore. Will I damage the flywheel if I try to crank it again, or should I just replace the starter? I hear it is a tricky job - Bentley's refers to a "ground down" 16mm wrench to get the top bolt out. Any words of wisdom? Thanks- Tim 1990 750iL 105K