New LS1 Owners - Newbie Tech - Desperate for help!!!!

Short version: When i went to start my motor a loud noise happened and it broke the starter where it bolts up.


Long Version: I tried to start my car and it broke the starter on the inside bolt hole. It also broke the outside bolt hole on the block. so i got a new shortblock nd put it in and went to start it and a loud noise happened and thank god it just broke the starter this time. What could possibly be causing this to happen? i noticed one of the starter bolts are bent but im guessing that happened on the first go around and wouldnt cause it to happen again. Any ideas would be helpful.

Well I would use new hardware to ensure straightness. What transmission? Could be a Flywheel type issue. I only broke starters on SBC type motors when the timing was physcially retarted in timing so much it kicked back and broke it.

M6. but this seems to be an issue for these motor is what i understand. Is it as simple as shimming or what? anyone else had this problem on a LS? thanks for your help. timing is dead on. idk what to do to fix it