It's probably a good idea to have a little lube on it. More importantly though, is how you install the timing cover. Just start the timing cover bolts...don't tighten them. While the cover is loose, install the harmonic balancer. This way, the balancer will center the timing cover for you. If you don't do it this way, it's possible that the seal won't be exactly centered on the balancer snout. Once the balancer is on(or at least started far enough to center the seal) you can tighten the cover down.