Melted common wire in boat wiring harness.

[juicegoose]

I recently moved my batteries from the rear of the boat up to the center console(07 2110 nautic star). While I was under the dash I noticed that the black common wire that goes from the gauges and switches back into the main wire harness was loose and had obvious signs that at one point it had overheated.
I will begin some basic troubleshooting to ensure there isn't still a fault but does anyone have a broad Idea of what could cause this? The only fuse in the system is a 30a main on the power feed to the panel and gauges.

Also If I wanted to replace the wire with fresh wire how do I remove the existing wire out of the harness connectors?

 

[bruceb58]

Re: Melted common wire in boat wiring harness.

What gauge wire is this? Is this the only common wire that goes into the harness is there another one from the fuse panel?

 

[juicegoose]

Re: Melted common wire in boat wiring harness.

It is a smaller gauge wire. 12-16. The wire is part of a main bundle that feeds the switch panel and gauges. I don't have a fuse panel per say. Each switch has its own fuse and the main power feed to the switch panel/gauges is fused from the battery via a 30 amp main fuse.

 

[bruceb58]

Re: Melted common wire in boat wiring harness.

Even a 16 gauge wire should be able to handle 30A without melting. It's not a recommended size and you will have a ton of voltage drop but it shouldn't melt.

As far as your harness is concerned and replacing the wire, you could just run another wire outside the harness back to the battery. You could just remove the end at the helm or even leave it connected if you want.

 

[juicegoose]

Re: Melted common wire in boat wiring harness.

True but I would like to replace the original wire so I can unplug the various harness connections and it be with it.

 

[UncleWillie]

Re: Melted common wire in boat wiring harness.

I recently moved my batteries from the rear of the boat up to the center console ...

When you relocated the Batteries did you also run new, even larger, Battery Cables back to the stern.
If you are starting the engine on the House Cables to the helm, smoke can be expected.

 

[juicegoose]

Re: Melted common wire in boat wiring harness.

This melted wire is old its not a recent event. Yes i did increase the size of battery cable per manufacture spec

 

[Grandad]

Re: Melted common wire in boat wiring harness.

I noticed that the black common wire that goes from the gauges and switches back into the main wire harness was loose and had obvious signs that at one point it had overheated

Just being loose can cause a wire to overheat even when carrying "normal" currents. Fuses can't protect from such failures. This is the reason that many jurisdictions are now requiring the installation of arc fault circuit interrupters in house circuits. AFCI's will disconnect power if an electronic sensing circuit recognizes the signature wave form of an electric arc that can cause a fire that would otherwise go undetected. - Grandad

 

[foodfisher]

Re: Melted common wire in boat wiring harness.

That melted wire in the harness may have taken other wires with it. Just sayin