Crank gear not seated.

So I put a new timing set on the slant and short cut the timing cover gasket so it leaked. Never enough time to do it right but always enough time to do it over, right? So now I'm pulling the oil pan too and doing them both right. When I got the timing cover off I noticed the chain didn't look straight. Looked around the crank gear and saw about 1/16" of shiny shaft behind it. Thought when I pulled the damper in it would push the crank gear down too? The crank gear slid on about half way with a couple of light taps so I finished installing the cover and then, slowly and carefully, pulled the damper in with the crank bolt until it wouldn't go anymore and the pulleys all lined up. Is there a tool to install the crank gear? What do you guys do? Any and all advice will be greatly appreciated!