January 22, 2017

I'm trying out a fancy new sensor bilge switch

Greeting skippers,

Here we are in the dog days of winter. Rain is falling heavy on the shoreline of southern California. The ocean is a chaotic mess of wind and angry swell. I for one could not be happier. The reservoirs are filling up!

But there's not a lot of sailing going on... So, in the interest of keeping busy, I've taken it upon myself to replace my bilge system. Usually I go with the classic float style switch, but this time - I decided to go with a fancy new electronic sensor switch. I got a Water Witch electronic sensor.

I went with a pretty standard pump. A West Marine 800gph pump. Apparently, these go out every 3 years or so. I just hit year 3 and sure enough...it crapped out.

So anyway, I wired up this new setup last month and its working great so far.

There are some advantages to this system, so I thought I would share my thoughts.


install electronic bilge switch
My filthy bilge with a new pump and a new sensor (black box in the back)


Here you can see I just put in the new West Marine 800gallons/hour pump. Normally, I have a float switch adjacent to the pump. When the water in the bilge rises, the plastic float arm rises also and this triggers a signal to turn on the pump. The problem was, my bilge is a bit too narrow. The arm of the float often touched the walls of the bilge as it was moving up or down. This made for an inconsistent system, as the float sometimes snagged and couldn't rise.

So, this is why I decided to opt for this new, smaller electronic sensor.

I bought a Water Witch electronic sensor - the Model 101 (12V DC). I found one at Marine exchange in San Diego for about 40$. There are no moving pieces.
Water witch electronic bilge sensor



When the water hits the large metal disc (see photo) then the signal triggers and the bilge activates.

What is cool about this type of sensor, is you can install it wherever you want (any height and any spot in your bilge). In a restricted bilge space, it is nice to have options.

Apparently you need to clean the metal disc from time to time. (If the disc is too dirty - a current won't go through). Although, this hasn't been an issue thus far.



electronic sensor bilge
heat shrink wire butt connectors

Oh and another thing... I finally did my wiring the correct way. I used these heat shrink butt connectors. In a bilge, any amount of exposed copper wiring will rot out quickly. These heat shrink deals are the best way to keep your wires from rusting out. Definitely worth the extra dollar.