My god, this is first ever case i have seen in my life. Its nearly impossible for that bolt to break off. Ya - thats a flywheel. It is a clear case of fatigue failure. Now the question is why did they repair it. They should replace the flywheel. Dont let this case go off easily Ashish. Contact all fiat top brass and let them know about this. Flywheel breaking is a very rare and bad case - fiat has to take a note of it and figure out if all the flywheels of this lot were faulty. Ask them for refund and a brand new flywheel. Tell them clearly that you dont want to risk a high speed diesel engine with repaired flywheel that has already come off once.