As Sam said, the finger wheel may be put on wrong, or the faceplate may be interfering with the dial, or it may be that the lubricant has gummed up. The gears might be not meshing properly, or the governor spring might be lost or broken. Lots of possibilities.
This guy repairs dials for $6.00 (yes, six dollars!)
Steve Hilzs The dials are very common and can be found in most collectors' parts bins.
