Rubbing or rattle? Two different sounds with different causes. Rattle...flexplate cover, starter heat shield, loose fan bolts, heat riser, loose air cleaner nut or air cleaner not centered on carb, loose bolts on core support, fender braces, or elsewhere in compartment.

Timing chain is easy to diagnose by rotating crankshaft first in one direction then the other, noting how far you can turn without disturbing the position of the rotor. It would have to be pretty loose to slap the cover.

TOHCan's suggestions will help isolate engine/drivetrain from body noises.