Info on Aft Bilge Alarm

[sasquatch]

Hi all. I just accepted delivery on a 2000 460 Sundancer with Cummins diesels this past Friday. On my way to my home port the following day, the 'Aft Bilge Emergency' alarm kept going off. Needless to say, this got my attention. I looked in the engine compartment and the sump box in the salon, but both are bone-dry. My thought is that it must be a float switch that is getting stuck/ Here are my questions:

1. Is it possible to isolate which pump / switch is causing the alarm to go off? It only happened when I've been running. After shut-down, the alarm shuts-off.

2. Is it possible to replace the switch or does the whole pump need to be replaced?

Thanks for any advice or suggestions in advance.

Sas

 

[tbirdvet]

Can turn off the circuit one of the pumps and try running again? This may help isolate which one is the issue.

 

[sasquatch]

Hadn't thought of that as I'm not very good with anything electronic. I'll see if I can figure that out by going through the schematics.

Thanks for the advice.

 

[murraybeck]

Normally the high water alarm is activated by it's own float switch. This is located near the lowest point bilge pump, but sits higher up in the boat, maybe on a bracket, or just above the bilge sump. It turns on the bilge pumps (usually all of them) and the alarm.
If it is turning on without having water float it up, it could have some debris lodged under it. I had one that was installed facing forward. When you planed out it would flip up, activating the alarm. It is possible that it's located somewhere aft on your boat.
Hope that helps.

 

[chumbley]

I had a similar problem on my 2000 340. Everytime I went to go up on plane, the emergency bilge pump alarm would scream at me.

What I found is that in addition to the mid-ship bilge pump (shower sump and A/C condensation), there was another bilge at the rear of the rear stateroom. My mid-ship bilge wasn't working right, and had water in the sump. When I accelerated the boat, the change would cause enough water to shift to the rear sump that it would activate, and any activation of this pump triggers the alarm.

Fixed the mid-ship sump bilge, and my problem (well, that one) went away.