I am replacing the oil pump belt, and discovered that I have a small oil leak inside the oil pump belt cover. Minor, but enough that the turbulence from the belt throws the small amount of oil around and makes the belt oily. It is hard to determine where the oil is coming from, but the seal looks dry, while the inside of the gear is wet and the two bolts heads inside the cover have oil drips on them. Any thoughts on the likely leak source, and how to fix it, are greatly appreciated.