the crank bolt should be TIGHT up against the pulley.....
removing the crank pulley should be pretty easy for you right now.... remove the bolt, pull the pulley off and inspect the key and keyway on the crankshaft to make sure it is not damaged... then inspect the crank pulley and make sure the rubber isolation is not breaking down... if all that is good... re-mount and install a NEW crank bolt and torque to 150 ft/lbs + 90 degrees....