Well if you can get the bolt loose with an impact gun that would be best. You don't want to tighten the bolt up with the impact gun however, for this you'll want to use a torque wrench.

Nothing will be messed up if the crank turns slightly. You will need to somehow hold the flywheel when you tighten the crank bolt. There is a tool for this but a large screwdriver or prybar will work. You may need a friend to help you for this...be careful not to break any of the starter ring teeth.


Nate Breece