Bilge Pump Warning Light
Revised by BoatUS editors in April 2012
The sound of an automatic bilge pump is usually drowned out by the other sounds of a boat underway, but knowing when the bilge pump runs can be essential to the safety of the boat. It lets you catch a sudden leak immediately, long before it is under a foot or more of oily water. Noting a decreasing time between cycles is also an effective reminder of the need for servicing a stuffing box.
Make it Bright
It is easy enough to add a warning light that visually announces when your bilge pump is running. Any 12-volt panel light will work as long as it is bright enough to be seen in sunlight. Red is preferred.
Locate the warning light where it will get the helmsman's attention when it comes on. On a powerboat that usually means somewhere on the instrument panel. The face of the bridge deck is often the most visible location on a sailboat. Panel lights cost only a few dollars, so a second one located in the captain's sleeping cabin can provide welcome reassurance.
Wiring is straightforward as long as the pump has a separate float switch. Use a step-down crimp butt connector to connect one side of the light into the circuit between the switch and the pump. Connect the other side of the light to ground. When the float switch closes it will energize both the pump and the light(s).