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Ask K. Kergan Your Own Question
K. Kergan
K. Kergan, Marine Mechanic
Category: Boat
Satisfied Customers: 1031
Experience:  24 yrs exp. Inboard/Outboard mechanic Mercury/ Mercruiser, Volvo Penta and OMC, Johnson/Evin.
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My boat is a 2012 Rinker Captiva with the Mercruiser 5.0

Customer Question

Hi Jeff, My boat is a 2012 Rinker Captiva with the Mercruiser 5.0 liter engine and an SPX 3615 "Electronic Float Switch" bilge pump. Got home from the lake today and I heard the bilge pump running but could not turn it off. The switch on the dash has two positions (manual/auto) and the light on the switch was on. Drain plug was out of the boat, bilge was bone dry, keys out of the ignition, switch in either position. The bilge pump would not turn off no matter what. I disconnected all of the wires from the dash switch, but that did not help. Finally got the pump turned off by disconnecting it from the battery. What do you think the problem could be? Thanks! Wes
Submitted: 1 year ago.
Category: Boat
Customer: replied 1 year ago.
It is possible that the SPX 3615 is only part of the bilge pump assembly. It is buried way down there and that is all I could read. There was also some kind of red pump cartridge assembly, but I don't know what it is. I'm wondering if I just need to replace the bilge pump assembly, or if there might be a more complicated gremlin hiding down there like a short or something. I truly dread having to take it to the boat dealership for service because it takes them weeks/months to get anything accomplished. BTW, I am pretty good hands on DIY mechanic.
Expert:  K. Kergan replied 1 year ago.

Hi, my name is Kerry

Most bilge pumps have a float switch connected directly to the battery bypassing the switch on the dash.

This is done so that the pump works when the bilge fills with water even if you aren't there.

The float switch is stuck on, it may be no good, or it may have some junk holding it up.

The cartridge is probably the float switch.

Customer: replied 1 year ago.
Hi Kerry, Thanks for your quick reply to my question. I'm going to order a new float switch from and swap it out in a couple of weeks (Just too hot in Houston to do it right now). I will post a reply at a later date and let you know if that fixed the problem. Thanks again for your help! Wes
Expert:  K. Kergan replied 1 year ago.
Sounds good.
I should have posted the last reply as an answer, I don't think there's a lot more to say.
Don't bother rating this answer until you verify that it's the float switch.
Catcha later.

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