Electrical Connection for Nav Lights

[Tom_F]

Is it OK to have a 12v electrical connection outside the boat and exposed to weather if it is protected by heat shrink tubing?

My Jeanneau SO 40.3 has the red and green nav lights mounted to brackets attached to the pulpit. The nav lights are separate lights not combined into one unit. I need to replace them for a few reasons and want to upgrade to Hella NaviLED PRO navigation lamps. These have a long (2.5 m?) cable that comes out the back to connect to the boat’s wiring - very similar to what I have there now. The cable on each of the existing lights is routed along and zip tied to the horizontal pulpit railing and then enters the vertical portion of the pulpit through a grommet.

The problem is, there does not appear to be any slack where I can pull the existing cable out, connect the new lights and then tuck the new connection back into the pulpit rail. Will the electric connection be sufficiently protected if I cut the existing cable, connect the individual wires in the two cables with heat shrink butt connectors and then cover the whole connection including both butt connectors with heat shrink? I would zip tie that to the rail like the original but it would be exposed to weather and not buried in the rail. The option is to trace and replace the wiring back into the interior of the boat, which is not a terrible idea but will take more time now than I have available right now.

Thanks.

[Cheechako]

Yes but use the good butt connectors with the built in shrink tubing that not only shrinks but oozes goop into the seal. They are a bit expensive, maybe $.80 each? but worth it for that application or underfloor damp bilge pump wires etc.

[Paul Elliott]

I would use the adhesive-filled connectors and heatsink. I have that arrangement on my bow bi-color light and it has held up for years.

[Tom_F]

Thanks. I only use 3M adhesive-lined connectors and adhesive-lined heat shrink so I have that covered, but thanks for the reminder.

[Redline452]

I did the same upgrade to the Hella NaviLED PRO on my SO 45.2 (largely because the original fixtures' $15 long-filament bulbs kept dieing from vibration rather than actual use). They did have just enough cable to reach down the pulpit, back through the anchor well and barely past the cable glands into the sail locker. Use the old cable to pull a fish wire which then pulled the new ones through. Without a sail locker, you should have more than enough cable to reach a splice/junction well inside the boat.


If you coil up and zip-tie the excess on the new lights, you can do the splice/heatshrink/ziptie method now, then fish the new cables down into the boat later when you have time and a hankering to do a "boat project".



Do check the lights work before shrinking everything - they are polarity sensitive which I discovered after making one of my splices. And depending when/where your Jeanneau was built, "blue" is "ground/negative" and "brown" ("marron") is "hot/positive".

[knockabout]

hopefully they are made with tinned wire and your boat has tinned wiring / slide on your self sealing shrink tape sleeves, solder your wires to make the join, when the solder cools slide your shrink tape over the join and heat to shrink and seal your soldering handywork, protecting with uv stable pvc electrical tape that matches the colour of the frame the wire runs along looks tidier / if your join is likely to be stressed( brushed past or ropes accidently pulled across it) uv stable wire ties(matching colour of course) should last as long as the nav lights. we have a waterproof submergible nav light on the port side showing a rusty water mark on the inside of the lens so sometime in the near future we will be practicing the joining technique ourselves. if you write the day of joining in your ships log be interesting to see how many sea miles your wiring repair lasts for

[Tillsbury]

I did a splice like this for an underwater pond fountain pump. Cut back to clean wire, twisted and soldered together, then covered each connection with heat shrink. I then slid another cover of the glue-type heatshrink over the whole lot and secured it. Lasted completely underwater far longer than the pump.

[RaymondR]

I use a hot melt glue gun to smear hot melt over the join, then slide the heat shrink over and use a heat gun to remelt the glue and shrink the heat shrink. The excess hot melt squeezes out the ends and can be trimmed off when it cools.

[Tom_F]

Thanks everyone for the advice. While I don’t have a sail locker like the 45 I’ll see if I can locate where the current connection is and leverage that. I never would have thought of hot glue. Great idea.