Forward bilge alarm

[Phudpucker99]

Howdy folks... I have a 1-year old 310SLX and loving it.  But I'm not getting straight answers from the dealer regarding an annoying alarm that kicks in almost every time we go out.  I assume rain is getting into the forward bilges (under the mid-boat floor compartment), and everything's fine until we get up to about 10mph and all hell breaks loose with a screaming alarm.

I realize it's happening due to the rainwater surging backwards and kicking off the rearmost float-activated pump, but I don't understand why the alarm needs to activate if the pump's doing its job properly. At the moment I'm stuck with manually lifting the floorboards and hand-pumping the water out - very annoying as it happens frequently.  The dealers' guys all seem to think this is normal - which seems like a basic design flaw if it is.  Any similar observations or suggestions?

[CommanderB]

Yep, well intentioned design flaw.

I have the same on a 350 SLX - rainwater if I leave the covers off or washdown water sits in the forward bilge and surges forward tripping the built in float switch and sounding the alarm while the pump runs, normally only maybe 10s.

It is working as designed, if the forward bilge is full then the alarm is a good idea. But under many conditions the alarm goes off unnecessarily.

There are a few ways to solve this, but you shouldn't have to do this on a 1yo boat.

You can cut the brown+white wire on the pump. The pump will still work automatically but won't sound the alarm. You won't know when its working, but you also won't know if you have high water in the forward bilge.

You can wire the brown+white to a light to alert you silently, or to a manual override switch and run the pump manually before you go out.

I took a rather extreme approach (on a 5yo boat) and installed an additional bilge pump in the forward bilge. I teed in to the shower sump (which never gets used) with a non return valve. And wired it to run with the main bilge pump, which is auto but without alarm. The pump will run dry sometimes, shortening its life, but it clears the forward bilge such that the original pump with alarm never sounds. I am pleased with this solution, but it is not something you should have to do on a new boat.

Thinking about it you could probably wire in a delay switch, so that the alarm only sounds after the pump has been running for x seconds. That might be the most elegant solution. But not something you should need to do on a new boat.

Good luck!