Or we could always answer the original question: The manual doesn't really state much beyond removal and replacement, except for how to bleed the oil pump. You can find that starting on page 3-4. This is necessary whenever there is a disturbance of the oil system, i.e. rollover, run out of oil, line removal. This seems like it would also prove that the pump is functioning (sorry, never had one), but if nothing else, you should be able to kick it and have something come out the hose (when not running).
As you can tell most people around here don't trust them and remove 'em upon first sight. If you really want to keep it and still have reliablity, consider replacing the pump every couple of years, bleeding as necessary.