2000 Chevy S-10 transmission

The transmission went out in our S-10 last fall, it sat all winter outside. We had the transmission replaced this spring, a week later the fly wheel needed to be replaced, then it started leaking oil, the oil leak was coming from a bolt that held the fly wheel on that had come out, but the bolt wasn't stripped, then over this past weekend the truck wouldn't start. Had started replaced and the hole the holds the bolt for flywheel fixed today, but still leaking oil, Any ideas? I was told by mechanic the oil was leaking because of bolt in flywheel came out? Also can the flywheel with a bolt loose cause starter to go out?