’91 Accord crank pulley rubbing against timing cover

This is more common than you might think in fact I see it all the time. Many times it is a result of not installing the lower cover correctly but sometimes the lower cover will warp on it’s own and come into contact with the back of the harmonic balancer especially if it becomes contaminated with oil. A good way to prevent this is to install all the fasteners that hold it in by hand first and run them down evenly instead of tightening them down all the way one at a time.