Bilge pump problem

[dutchman]

My new boat has been sitting in my warm garage all winter, hasn't moved for 6 months. The other day I hear this humming noise coming from the boat. WTF, the bilge pump is running. How the heck would it start running while it's been parked for 6 months?? Only way to make it stop is pulling the fuse. Today I run the engine on the driveway, everything works great except the pump won't quit. Put some water in bilge and pump sucks it dry no problem. But still won't stop running. It's an auto pump with a manual switch.

Is this a boat manufacture problem or a Merc problem?
I have no dealer near by so just looking at options on what to do.

 

[Lazy Daze]

This is a boat issue, not an engine issue (Glastron?). The bilge pump has nothing to do with the engine.

Not to say this never happens, but I've never heard of a float switch failing in the ON position. The first two thoughts are... something stuck under the float or the switch on the dash is on. The only other things I can think of are a shorted wire in the float/pump wiring or a failed switch.

 

[ZZ13]

This is a boat issue, not an engine issue (Glastron?). The bilge pump has nothing to do with the engine.

Not to say this never happens, but I've never heard of a float switch failing in the ON position. The first two thoughts are... something stuck under the float or the switch on the dash is on. The only other things I can think of are a shorted wire in the float/pump wiring or a failed switch.

Dennis my shower sump float switch shorted out and ran the pump 24/7. I just swapped out the switch and all was good. So it can happen.

 

[Lazy Daze]

Dennis my shower sump float switch shorted out and ran the pump 24/7. I just swapped out the switch and all was good. So it can happen.

Well... then I will change my statement to "It's extremely rare for a float to fail in the ON position".

But seriously, thanks for posting that, Bill. Given my profession I tend to see more things than the normal boater, and this really is the first time I've personally heard of this. It's good to hear more experience from out there in internet-land!

A couple more thoughts...

Obviously I can't fully speak for how Glastron does things, but the float switch should be wired direct to the battery. Which fuse did you pull? The one for the switch at the dash or the one for float switch? Depending on which fuse you pulled, that can help to narrow down whether the problem lies in the float switch side of things or the manual switch side of things.

 

[dutchman]

thanks for info, even though it's not a searay.
The dash switch is off. If I turn the switch on, I can hear the pump do a little hiccup, and keeps on going. The switch is also lit up regardless on or off, showing the pump is running.
Right at the battery, there are several separate wires with inline fuses. One of them reads bilge pump and that is what fuse I pulled. That wire runs directly to the pump.

 

[Lazy Daze]

OK, that information helps narrow it down. The wire should go to a float switch, then the pump. You can forget about the dash switch side of things. It's sounds like either a stuck float switch, shorted wiring between the fuse and the switch or the switch, itself.

Edit: Forgot to mention that if you don't have a float, then you have an auto sensing pump (looks/senses for water every few minutes).

 

[QT1]

Working on my bilge pump problem also. Found a broken wire, set the dash switch to manual, added some water in the area of the float switch, lifted it up, nothing. Someone suggested wiring the pump directly to the battery to see if will run. If it does, it would mean float switch issue. If it doesn't run, pump issue. By the way, this is the pump in between the 2 engines at the front.

 

[dutchman]

Ok verified there is a float switch, then the pump. So pulling the fuse on the direct battery line turns off the "Auto" function. The pump still works on/off with the manual dash switch. So at least it's narrowed down to the float switch and that will not stop boating season right around the corner (yep 7 months of storage, lakes still iced over).
Now the next step? No dealer near by so looks like I fix myself. The only way I got a good look was with my GoPro on a selfie stick. Will have to pull the bench seat backrest and hopefully reach under there.
Thanks Dennis for the pointers

 

[dutchman]

Well all fixed and back to normal. If anything, learned how my boat is put together.
For better access, I removed the cushion of the bench seat backrest. Then the bottom center section of the seat. It's an integrated cooler and part of the floor panel. quite easy actually. Then I could sit right in front of the engine. That will come in handy for future maintenance.
Swapped out the bad switch, plugged in the new one and works like it should.
Switch is a Rule 40A. Tested and definitely fail in the on position. Can't actually see in the wire connection box since it's sealed, but something must be crossed in there. Can't break it open since it needs to be returned.
Dealer is 2 hour drive away, and I did not feel like hauling the boat all over for a simple problem. The dealer is super busy this time of year, so he sent me the replacement and I did the labor.