yeah i thought it was his fault but he said the bolt was rusted pretty bad and that it must have snapped because of it not because he over tightened it or he installed wrong he told me since there was a warranty on the motor that i should call the place and tell them about it i did and they said it had to be the mechanics fault that they wouldn't replace and the mechanic said it wasn't his fault that he wasn't going to pay to have it fixed. so i guess i'm pretty much screwed so i guess i'll look for a head now thanks everybody for their input