Bilge pump mystery

[Molly]

I have a good one this time. I have a 2006 34T, twin screw. My bilge pumps have been switching on for apparently no reason. No water, I even manually turned the float switch on and off. Later, by reading, that my alarm will automatically turn my bilge pumps on if my battery voltage drops down too low. Now, I charged the batteries and the alarm went off, but the middle pump still is on. WTF!
Again, no water and I manually flipped the float switch back and forth.

 

[High Wire]

Brand, Model, pump and switch?

 

[O C Diver]

Without knowing the pump and switch manufacturers, I'm guessing it's in the high water alarm microprocessor. If more than one pump is effected and the common link is the high water alarm, and it can turn the pumps on, that's where I would start looking. IMO, there are someplaces where networking systems doesn't generate reliability. With bilge pumps, I think simple is better.

Ted

 

[sdowney717]

I use standard non electronic pumps and switches.
Since I have 5 bilge pumps, any one pump can fail and I have backups ready to work.
2 in one compartment, and 3 in another.
One pump's switch is set lower and is then the primary pump, the other switch sits higher and a third sits completely out of any bilge water. So failures of a lower in the water pump mean I have working backups.

They are all Rule pumps. I have taken apart old Rule pumps and even they still had not worn down their motor brushes past half way point. Every failure for me, with a bilge pump, has always been its water detection switch.

 

[Opu]

The OP didn’t say whether “flipping” the float switch turned off the running pump. A couple of weeks ago I was spending the night on Cheers and when I was going to bed I heard an unusual noise. After some investigation I discovered that the float switch in my midship bilge was activated and wouldn’t turn off. I cut a wire to the switch and the pump stopped. I took the switch out and verified that it was indeed jammed on. The faulty switch (Rule) was only about six months old so I took it back to West Marine along with the original receipt. They gave me a new switch, no questions asked. Also, they had reduced the price over the six months, so they refunded me the difference.

 

[Cigatoo]

These switches have a great reputation with commercial guys. No personal experience. I think that I might try one.
https://www.groco.net/as-100

 

[meridian]

You didn’t say what pumps you have. Some will automatically turn on for a few seconds to check for water in the bilge. This happens every 5-10 minutes or so.

 

[Catbird]

These switches have a great reputation with commercial guys. No personal experience. I think that I might try one.
https://www.groco.net/as-100

I'm using a Jabsco version of this same type switch. Like the Groco, there are no moving parts or electrical components immersed in bilge water.

59400 series Hydro Air Switch > Bilge Accessories > Xylem Flow Control - Let's Solve Water.

 

[Molly]

I've been troubleshooting all day! I definitely have 1 bad battery. Happens to be the one all 4 bilge pumps are connected to. My high water alarm automatically turns the pumps on if the voltage drops too low. I had to disable 2 pumps! The other 2 work fine. I will change out that bad battery this week. Then I have to splice the wires I cut! I love boats. The only thing I own that I can reach WAY down into the bilge with a pair of dikes and snip wires to stop a motor from running. Then I have to go back in and try to splice that same wire I cut in some God awful position way down in the bilge. And to top it off, it seems normal??

 

[Molly]

I could have just moved the power from the bilge pumps from the bad battery to a good battery!!!!!