I noticed on my new engine that there is a track where the con rod rides around inside the crank case. There are two spots, on the sides, where the rod actually rubs against the crank case, very slightly. I'm assuming this is normal and OK, but I figured better safe than sorry. So is this OK? (trying to upload pics, not really working).

Also, is it only the tension of the prop nut that holds the shaft forward? With the engine off the plane and no prop, the shaft can be pushed in far enough that the con rod rubs against the back plate. Is this also normal/ok? Edit Ok for this part I guess once the prop is on for the first time the shaft gets seated in the bearings and doesn't slide around.

Thank you.