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Bilge Pumps are important safety features on boats that can help to keep them from sinking. Sea Eagle has three bilge pumps and they all work very well, but I noticed water collecting in the high bilge well just forward of the engine (during a routine check). A quick taste test of the rather nasty looking bilge water confirmed that it was fresh water (condensation from the Air Conditioning) and further investigation revealed that the high bilge wasn’t draining into the low keel bilge.

Disassembled Ultraswitch float switch.  The float is on top of the white high level bilge pump.

Disassembled Ultraswitch float switch. The float is on top of the white high level bilge pump.

A quick check of the excellent Nordhavn Owner’s Manual confirmed my suspicion that there was an open drain line from the high to the low bilge and an inspection revealed that a wet oil absorbent pad was effectively blocking off the drain. I removed the now slimy pad and most of the water drained out, but there was still about an inch left. Hmmmmm? I made a couple of trips up to the pilothouse, turning the High Bilge Pump on for a minute, then returning to the engine room only to find the water level about the same. More Hmmmmmm?

I turned the pump on again, left it running and returned to the Engine Room to find that the High Bilge Pump was working great, but water was flowing OUT of the drain to the lower bilge! After a few seconds of OMG, we’re sinking… I checked the lower bilge and it was full of water too. DOH! Hence the post on the Bilge Sensors.

Fully assembled Ultraswitch float switch.  Testing by inverting.

Fully assembled Ultraswitch float switch. Test by inverting.

Nordhavn uses very high quality bilge sensors (Ultraswitch Senior float switches), which are pretty idiot proof, but they need to be tested and cleaned periodically. I removed the sensor (see photos), cleaned the crud off the float that was preventing free movement, reassembled the unit and it worked like a charm. I also took the opportunity to replace the pair of 9 volt batteries in the high water alarm panel that Jeff Merrill had told me about many moons ago.

Have you tested your bilge sensors and pumps recently? 😉