[RichardJ]

1. It didn't do it on the old starter.

2. He changed the starter not the distributor.

3. Too much timing isn't going to loosen starter bolts.

Did you shim the starter properly and is it noisy? Was it loose the first time because you forgot to tighten the bolts?
You need to check the ring gear to see if the loose starter caused damage.
What was wrong with the old starter that it needed to be replaced?