Beware of old wire bundles, smoking and possible fire

[HIRSCHHORN53]

Recently I was down in the bilge doing general cleaning and manually ran the bilge pumps to make sure they are operating properly. I noticed some smoke coming from a wire. I stopped, let it cool down then tested again. There was definitely smoke coming from some wire and even noticed a wire turning bright orange. What appears to have happened is that SR takes long wire runs and folds and bundles together and then very securely attaches multiple wire ties (in this case 3) to secure wires to the bilge deck so no movement (very neat and clean). The folding of the wires and the securing with ties cause more resistance in the wire. Over time, the wires develop heat and can eventually burn away some of the protective insulation. This is what appears to have happened in my case.
Here in the Northeast, we have had tremendous rain which can partially drain into the bilge. My pumps do a great job to drain but also have built up excess heat on the wires.

The point of my little story is that it's important to check your wire bundles to see if any excess wear or deterioration on the insulation. In my case, if I hand not run this test and seen the smoke myself, this could have potentially caused a fire in my bilge when I was away from the boat. I have diesel so not as explosive as gas but still not something you want have happen.

Over time, everything wears out, including wiring. It pays to give a good once over on your wiring so see everything is in order.

I have since spliced in new wiring on my bilge pumps to make sure everything is ship shape.

 

[Mr Salt]

Thanks for sharing your findings with us. All Sea Rays face the same problem as wire bundling is SOP. I will certainly check my wires bundles for the same issue.

 

[mawyatt]

Peter,

If the wire was glowing orange this indicates a serious problem. For a wire to glow and burn the insulation off the current must be very high, much higher than any normal rating. I would venture to guess that maybe something downstream from the powered (battery) end of the wire is trying to draw excessive curent. The extra length resistance of the wire used for the bundle isn't the problem, you have something else going on. Please take some time with a good VOM and see if you can trace down the cause of the excessive current demand.