I assume that you mean the power bilge pump. First see if the motor is running. If so, see if the pump diaphragm is being depressed in a reciprocal manner by the motor. I have had a pump where the nylon gears broke and although there was nothing wrong with the motor, the Italian manufacturer did not offer a component replacement for the reciprocal gearbox. Bummer! I had to buy the whole unit.
If the motor is running but the pump is not working, remove the pump cover (left side). If you do not have replacement rubbers for the two valves, you can either turn the existing rubbers upside down and reinstall them, or simply cut new rubbers from a blank sheet using the old rubbers as a template. You can usually get to the bottom valve flap easily using a jeweler's Phillips headed screwdriver. The top one is tougher and I have had to resort to a Phillips screwdriver bit in a ¼" socket. It is usually the bottom rubber that gives the problem because it holds the weight of a column of water and develops a "curl" after a while. If the valve replacement does not work, pull out the hose from the sump and replace the one-way valve in the "strum box". These are usually easy to find at any marine supplier in the USA. Messy but it is only "grey" water.
SV DoodleBug SM #331
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