Bilge Pump will not stop

[ChrisHunter]

I have a 1992 Hunter 30. As we were anchored out, my wife turned on the DC water switch. The bilge pump started to run. Removed the flooring and the bilge was dry. I played with the float switch, but no luck. After knocking on the bilge, I cut one of the wires to the bilge pump and it stopped.

Thinking the float switch was bad, I purchased a new one and installed it. Reconnected the wires the bilge pump started to run again. I also disconnected the wires to the float switch hoping this would stop the bilge pump, but no luck.

Do I have a manual bilge pump switch that I do not know about? Could not find it in the manual.
I thought the wires to the float were the primary power for the bilge pump, but I am wrong.

Any suggestions would be helpful as it's good to have a working bilge pump.

Thanks

 

[Don S/V ILLusion]

Check to see what effect flipping the float switch has on voltage at the pump motor. Could also be an improperly PO wired float switch

 

[Ralph Johnstone]

As we were anchored out, my wife turned on the DC water switch. The bilge pump started to run.

@ChrisHunter , after reading your post my first thought was to seek the services of a priest as this unusual circumstance was very likely the work of an evil spirit.

However, after reading @Don S/V ILLusion 's comment, I was willing to concede that a misplaced electrical connection was a more earthly explanation for the faulty bilge pump operation.

The first qustion which must be addressed is "is this the first time you have witnessed this unusual situation ?" Or has there been some finger poking in any electrical wiring recently. Your wording sounds like this is the first time you have turned on the water pump. We will need everything electrical to diagnose this problem. I would also add that this problem cannot appear out of thin air. It is the result of an incorrect electrical connection made at some time.

We'll let you clarify this but in the meanwhile I'll assume this is the first time you've turned on the water pump and seen this problem.
IMO, I'm thinking, specualting, contemplating, whatever, that a more likely place to find your previous owner's (PO) wiring error is behind your 12V wiring panel. The reason I say this is that the physical wiring to the one single bilge pump and the one single water pump are likely separated by a good many feet. I can't see accidently running the water pump wiring over to the bilge pump wiring unless the PO was out on a day pass.

If your 1992 12V panel is similar to my 1999 panel (guessing here), pull it out and locate the OFF/ON circuit breaker switches for both the bilge pump and the water pump :

My suspicion is that you will find the load wires coming off the water pressure breaker have a take off leading to the load wires of the manual bilge pump breaker or switch or whatever you want to call it. This is what causes the water pump switch to always deliver power to the bilge pump when turned on.

Sorry to get all electrical on you but you're going to need a bit of electrical knowledge and a cheap (or expensive) muiltimeter to get through this problem.

 

[Project_Mayhem]

Your bilge pump may have an internal float switch. Not likely, but possible

 

[danm1]

Exact same thing happened to me. I asked a boat owning friend with more electrical knowledge than me how to troubleshoot it and he said it's not worth the time given the cost of replacement pumps with internal floats on Amazon.. Just put in a new bilge pump. I did and it works normally.

 

[Ralph Johnstone]

Your bilge pump may have an internal float switch.

my wife turned on the DC water switch. The bilge pump started to run

It's the fact that the bilge pump started to run when the DC water switch was turned on. Gives me that nagging feeling that the two are electrically connected.

Maybe we can get the OP to switch the water pump ON and OFF a few times and see if they react together.

 

[Project_Mayhem]

It's the fact that the bilge pump started to run when the DC water switch was turned on. Gives me that nagging feeling that the two are electrically connected.

Maybe we can get the OP to switch the water pump ON and OFF a few times and see if they react together.

I'm not familiar with Hunters and I assumed that they may have put multiple pumps on one circuit. I like the way you think though. It's a definitely intuitive and shows that you have many years of experience

 

[BrianQ]

Your shower drains directly into the bilge so there is likely a switch in the Head to bypassing the bilge pump float switch, so the pump comes on when someone is using the shower.

Since your bilge pump comes on when the water pump is turned on points to there being a separate switch in the circuit for the reason above.

 

[Stu Jackson]

Ralph's systematic approach and others' input have value. Where you need to GROW is to learn how basic circuits and switches work and STOP cutting wires to stuff to try to solve problems because all you've done is broken something else. Finding out where the power is coming from is really important. And that's the job of wiring diagrams, owners manuals and digital volt meters, the easiest electrical tool to use known to man. There are many Boat Electrical nooks, but a good stsrter kit one is Charlie Wing's: Amazon.com

Good luck, please don't cut wires to turn stuff off --- learn how to disconnect the wire, your choice of which end.

Any suggestions would be helpful

 

[ChrisHunter]

Hope to be back up on the boat in a couple days. Will take a look at the electrical panel, but mine has many less options than the 1999 model.

Owning the boat for several years, we have turned the water switch on a hundred times without the bilge pump coming on.

Will continue to review and I post an update.

Thanks

 

[Ralph Johnstone]

Owning the boat for several years, we have turned the water switch on a hundred times without the bilge pump coming on.

Now it gets weird which makes it interesting.

When you are at the boat, could you please switch the breaker switch for the water pump OFF and ON several times and report if the bilge pump also goes OFFand ON ?

EDIT : Bit of an addendum there in that you will have to re-connect the wire you cut from the bilge pump back in post #1. Make it temporary with a wire nut as we're still in the searching phase.

Including any photos you can is always an assist.

 

[Ralph Johnstone]

Any chance you've got a copy of the original wiring diagrams for your 1992 Hunter ? If not, there may be a copy on line in the archives here. Anything in early '90's may have what you need for a wiring diagram.

 

[Davidasailor26]

Exact same thing happened to me. I asked a boat owning friend with more electrical knowledge than me how to troubleshoot it and he said it's not worth the time given the cost of replacement pumps with internal floats on Amazon.. Just put in a new bilge pump. I did and it works normally.

But the OP already swapped the float switch, so that’s not the problem, and a bilge pump will just run whenever it gets power, so that’s not the problem.

The fact that the pump ran around the same time the fresh water was turned on is too coincidental for me. And an original wiring diagram might, but after 34 years who knows if that’ll be right or just more misleading. My guesses are:

1. There’s a manual switch somewhere on or near the panel that accidentally got bumped when turning on the water pump
2. There’s a manual switch elsewhere, like in the shower that BrianQ alluded to, that’s powered by the fresh water circuit and accidentally got bumped
3. There’s some sort of short between the water pump circuit and the bilge pump circuit