Rear bilge pump float switch location

SteveCW30CB

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Joined
Sep 18, 2024
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17
Fluid Motion Model
C-30 CB
My automatic bilge activates continuously i.e., 20 seconds after the bilge is pumped out, the pump actives again but doesn’t pump any water….and so on. I think this means the float switch it located in a location even with or below the location of the pump. Shouldn’t the float switch be located such that it is above the pump? So my question is : where is the float switch located? Any insight would be helpful.
 
You don't mention what kind of boat you have.
Some of the bilge pumps used have the float switch function built in. They turn on every 2.5 minutes. If there is resistance from water being present, they stay on and pump. If there is no resistance (no water), they turn off. So we hear the "whirrr" sound every so faint, every 2.5 minutes. When the float function fails, the pumps usually will work manually, but not always. Either way, the only way to restore the float switch functionality is to replace the bilge pump, assuming this is the kind of pump installed in your boat.
 
Thank you for the info. I will pay closer attention to how often it turns on - I wonder if the interval can be changed to have it cycle less often. My boat is 2016 30 CB LE with 435 Volvo.

Steve
Annapolis MD
 
Thank you for the info. I will pay closer attention to how often it turns on - I wonder if the interval can be changed to have it cycle less often. My boat is 2016 30 CB LE with 435 Volvo.

Steve
Annapolis MD
Hi Steve,
I have the same boat and my aft pump has a Johnson sealed electro-magnetic float switch with pump.(no auto timed intervals) Pump will auto activate at times when under way and never shut off unless I turn it on/off at cabin helm switch. Only way I know is I installed a red alert bulb above helm sw. It illuminates when it activates. Have yet to find a replacement that will fit in aft tight bilge space.
I don’t even know where water comes from other than stuffing box drip, which happens to drip right onto sensor and even then it does not activate till water rises high enough for sensor to kick in. Still trying to figure it all out. Pump will always activate when I step to plane angle of attack,so I think there is another source of water intrusion foward that runs aft .
 
Hi Steve,
I have the same boat and my aft pump has a Johnson sealed electro-magnetic float switch with pump.(no auto timed intervals) Pump will auto activate at times when under way and never shut off unless I turn it on/off at cabin helm switch. Only way I know is I installed a red alert bulb above helm sw. It illuminates when it activates. Have yet to find a replacement that will fit in aft tight bilge space.
I don’t even know where water comes from other than stuffing box drip, which happens to drip right onto sensor and even then it does not activate till water rises high enough for sensor to kick in. Still trying to figure it all out. Pump will always activate when I step to plane angle of attack,so I think there is another source of water intrusion foward that runs aft .
I will check the pump brand to see if it is the same as yours. The indicator light is good idea, otherwise it would be on constantly and burn itself out. Is there a circular ‘bracket’ (just below the packing box) that your pump sits in? I have such a bracket, but my pump was laying in a hole about 4 inches in front of the bracket where the floor of the bilge is about 4 inches lower - so the pump was at the lowest point on the bilge. It was held in place only because the connecting wires are somewhat rigid. Im thinking it is supposed to be in the bracket?? I just recently realized (after having the boat for a year) that it was not activating automatically - turned out to be a blown fuse. I replaced the fuse and now it operates on the short interval I mentioned previously.

Does your forward bilge pump ever activate - mine does not. The owners manual indicates it should be located just fore of the motor….i have not looked for it yet. It’s a PIA routing around in the bilge!
 
I will check the pump brand to see if it is the same as yours. The indicator light is good idea, otherwise it would be on constantly and burn itself out. Is there a circular ‘bracket’ (just below the packing box) that your pump sits in? I have such a bracket, but my pump was laying in a hole about 4 inches in front of the bracket where the floor of the bilge is about 4 inches lower - so the pump was at the lowest point on the bilge. It was held in place only because the connecting wires are somewhat rigid. Im thinking it is supposed to be in the bracket?? I just recently realized (after having the boat for a year) that it was not activating automatically - turned out to be a blown fuse. I replaced the fuse and now it operates on the short interval I mentioned previously.

Does your forward bilge pump ever activate - mine does not. The owners manual indicates it should be located just fore of the motor….i have not looked for it yet. It’s a PIA routing around in the bilge!
Steve,
Ford pump is fore of engine and has not activated unless I manually turn on. I’ll check bracket set up Thursday when on board.
G
 
My pump seems to be malfunctioning. It was working as advertised I.e., turned on every 2.5 minutes to check what level, then shut off when no water detected…though this was somewhat inconsistent in that it ran for 30 seconds sometimes and ran only a few seconds other times. Then hours later, it turned on and off continuously….until I ‘reset’ it by manually turning it on and them off. I have no choice but to replace it as I can’t explain its intermittent behavior and don’t want it to operate in the continuous mode. I pulled the fuse in the meantime to prevent it from operating continuously. The only thing I can think of regarding the malfunctioning is that the pump is not level, it sits at about a 45 degree angle ( with the sensor portion facing up so it shouldn’t trigger unless the water is above the impeller portion)….just can’t get it level due to space and connection limitations. Anyone know if these pumps need to be closer to level to operate correctly?
 
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