Marlin sump pump & float switch

liinw8

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Thanks again to everyone for helping me choose (and now thoroughly enjoy) my new-to-me '99 Marlin! The shower sump pump and float switch don't work. I'm not sure if they're both shot, or if it's a wiring or fuse issue. Does anyone know where the fuses are? I only see the switch on the main electrical panel for sump pump, but I don't see any other switch or fuses. I assume the switch on the main panel delivers power to both the sump pump and the float switch without any other switches. For example, there's no auto/manual like there is with the other bilge pumps. Does that mean they're not wired directly to the batteries like the other bilge pumps? I want to check to see if a fuse may be blown, but does that mean I have to remove the main panel to check? I took off the panel and looked inside the sump box and to where the wiring comes out of from the lower bulkhead/panel, and the wiring to the pump and float switch is just wrapped with electrical tape (it looks like it may be original) and there's no play in the wires to pull out the wiring to check the connection where the pump wiring was spliced into the boat wiring or to test the connection without cutting or stripping the wires, which was going to be my next step, but if there's a fuse somewhere to check I'd prefer to do that first. Thanks!
 

Sketchywind

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I had similar issue with my shower sump on my grady 265. I removed the pump and float and bench testing with 12v battery. They both worked so it was the wiring. One wire had corrosion and not connected to float. Put it all together and works great. Lots of moisture in bilge, so that could be your issue too. The fuse is under the instrument panel. Remove panel and it's fairly easy to check fuses.

Frank
2001 Grady 265
 

jbrinch88

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First off, invest in some "wire piercing" probes. They'll enable you to trouble shoot electrical problems very quickly without having to remove connections/strip wires.

I've seen sump pumps wired many different ways. Most common way I would say is the float switch is not wired for 24/7 (directly to a battery). It is wired to a fuse block that gets power from a feed coming from the main battery switch, or House battery switch.

Also there is usually a "Manual" switch to power the sump pump either somewhere in the head or on the breaker panel. All depends on the boat make, or who ever has had their hands in the wiring.

I would say get some probes and make some 14g jumper wires with alligator clips. It'll make all your 12v troubleshooting a lot easier, especially if you're keeping the boat for awhile.

Just to throw this out there, there is a tool called a "power probe". Google Search it, one of the best things I own for quick troubleshooting. I work at a Marina and you can make easy money with this thing.

Good Luck.

Jason
 

Another Distraction

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Check the "sump pump" switch on the main panel. That switch may be your fuse and your switch all in one.

Liinw8. Are you handy with a multimeter?
 

liinw8

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I peeled off the electrical tape and found some exposed wire (which I'll have to clean up) and I'm getting voltage with the multimeter so I guess it's the pump. Thanks again.