My smith corona vintage typewriter ribbon won't advance. The left side is tight. The ratchet is not turning the bar. The square spring is not broken.The bar does go back and forth, better on the right side. I don't know how to lubricate the spindle shaft on the left side to make it turn more easily. The little ratchet is not grabbing as well as it might, and thus the bar is not turning. I can turn the bar with my fingers.