The oil is pumped from a hole in the saw body into the round holes in the bar and then goes through a passage into the slot that the drive tangs of the chain run in. Your problem could be that the bar isn't sealing against the saw body because of dirt or something is warped, or the passage from the round hole to the slot in the bar is clogged. The bar on the right has a small hole that is used by some saws for the oil. Most saws have thin metal plates that fit on each side of the bar. These HAVE to be in place if you have a bar like this and a saw that pumps the oil into the larger holes.