The water has to reach a certain level, before it will kick in automatically, unless you have a bad float switch. It is somewhere down on the starboard side. Check and see if something is blocking the switch, or replace it. A working bilge pump is a good thing to have.
For maintenance, change the plugs, change the oil, filter and o-rings/gaskets. Check your impeller wear ring, and replace if gouged. Also, grease your jet pumps, and consider an oem rebuild kit, to replace seals and bearings in the pumps... Good luck!