Repair Your Bilge Pump

How to test & repair your bilge pump?

by Conrad & Judy Kreuter

One of the most important safety devices in your boat is the bilge pump. The bilge pump is responsible for pumping from the boat any water that may have accumulated due to rain or leaks. Because bilge pumps are located at the bottom of the bilge, they are often overlooked. When was the last time you checked yours?

The bilge pump is only one part of the complete system for eliminating water. The float switch, electrical components and water outlet hose are equally important. The float switch is an automatic device that activates the bilge pump as the level of water increases.

The best method for testing the pump system is to fill the bilge area with water from a garden hose or bucket. When the float switch reaches its “turn on” height the water should pump overboard. As the level of water goes down, the pump should turn off. While the pump is working, observe the outlet hose for cracks and leaks from the pump to the outlet fitting. Many times the outlet hose is split allowing some or all of the water to go back into the bilge. Replace the hose if there is any doubt.

If filling the area around the pump is impractical, simply lift the float switch and listen for the pump to operate. This will check the automatic feature of the pump system. If you have a bilge pump switch at the dash, turn the switch on and listen for the pump motor to activate or watch for water to exit the boat.

If your pump only operates when turning on the dash switch, not when the float switch is raised, you will need to determine if the float switch is bad. The wiring and fuse could also be defective. Locate the fuse connected between the float switch and the battery, and check to see if it is blown. Also, check the condition of the wires from the battery, fuse holder, and connections to the float switch. If the wiring is good, the float switch will need to be replaced. It is best to replace the float switch with the same model so that you do not have to drill new mounting holes. Follow the manufacturers wiring diagram to install the new float switch.

If lifting up on the float switch in the bilge or turning on the bilge pump at the dash does not make the pump run, and the wiring is in good condition, the pump will need to be replaced. Try to find the exact replacement to eliminate drilling more holes in the bottom of the boat. Follow the wiring diagram supplied with the pump. Make sure waterproof butt splice connectors and fuse holders are used to wire the bilge pump.

Remember to test your bilge pump system on a regular basis. Covering your boat with canvas can also prevent your bilge pump from working overtime and draining your battery. Your IMD dealer can supply all the necessary parts and expert advise to help in repairing your bilge pump.