Running new electrical in '78 Hunter 27

[SailingFan]

I am updating the electrical in my Hunter 27, and want to basically rid her of all the incandescent lighting and replace that with LED. Is the following reasonable expectation, and what traps may I fall into with this plan of action that I may not anticipate already (for those who have already tried this)?

Further, I am considering replacing parts of the wiring itself, as well, in cases where I am suspicious about it (the bilge pump, for instance, will get a new dedicated wire run, as the old connections are theoretically possible to submerge in the bilge water and I want to move connections to dryer locales to prevent potential intrusion of brine along the wire sheathing interior. The wires are only a few inches long on the pump though).

I am adding a second, higher mounted bilge pump as well, so that I can increase the discharge rate should that be an issue one day (heaven forbid). I may use it as a quasi-shower (sit on a box and hand wash sort of thing) sump pump and let it double as an extra pump should water spill over the sump sides. It would be an emergency thing, but would need new wiring because the wiring is not currently in place for it. I think it is an 800 GPH pump (nominally, of course). The discharge hose for it is rather large, larger in fact than the one on the main pump.

I will be replacing the wiring to the spreader lights and the masthead or at least checking to see if it needs a firmly soldered and sealed disconnector section in a junction/bus bar box I am considering installing inside the cabin, below where the mast and deck connect - since dropping the mast is such a pain, I figured I may as well install this box while I am there). I am wondering if 16 AWG is good for the mast run, with a total of 18 watts per spreader of draw, and a round trip distance of 30 feet for the circuit, if I just replace the entire run, or if a smaller/larger gauge is better.

It looks fine where I can see the wiring, but I cannot of course see all of it yet. There does not appear to be any PO manipulation in the vessel wiring, outside of the engine compartment and gauges panel, other than the 110 volt section that is coming up below.

Additionally, though the LED draw should be far lower than what was already there and so supported by the original undamaged wiring, I am noticing that the lighting receptacles below decks have rust on them, which makes their conversion a no-brainer since receptacle replacement is already required (at about the same or similar cost to get them to LED, no less).

What I am wondering here is what sort of wire gage I should be expecting to use, as my wiring chart only goes down to 16 AWG (which seems large for LED lighting) if I supply all the LED lights on a single supply circuit for below decks (switched receptacles, of course).

I would use a separate circuit for the anchor light aloft, a single wire for the the masthead steaming lights, and a single wire for the spreader lights (so that would make 3 electrical wires within the mast, plus two individual coax lines for the radios).

I was thinking about this, and the longest run of wire would be to the masthead light, approximately a total of 40 feet from bus to receptacle, each way (and maybe less than the combined 80 feet). 16 AWG is probably more for structural support ( to keep the wire from pulling apart hanging and rattling around in the mast) than anything else at that low voltage and length, so seems reasonable for supporting the minor LED draw of the masthead LED, and the same for the 36 watts of the spreader lights. Even the steaming lights on the mast would take only minor wattage as LEDs, but again, as we are in the mast, I was thinking I could stay with 16 AWG or whatever was in there already (assuming it is fit for service) if I had to.

The next longest run would be about 50 feet round trip to the bow lights, though for the life of me, I don't know why Hunter installed those below the toerails! They seem original. I have been toying with what to do with them, because they really don't seem to fit the modern rules of lights on sailboats traveling in steaming mode. Still, as they are original, I don't know if anyone would give me crap about them.

I could just leave the lamps out and reconnect the wires to LED reading lights or something in the vee berth with a reroute and change to the bus label for those particular wires, and leave the hull fixtures sealed in place as they are, minus bulbs?

I want to replace the other 2 overhead lamps in the vee berth currently, which are again incandescents, with LED. The wiring is present and seems fine. It looks like a simple fixture change for them.

One thing I noticed on board was that many of the lights seem to operate only on 12 volt, while some others operate only on shore power. I am considering removing the shore power wiring entirely, and rewiring those lights and outlets with new wire all around, for pier use.

Currently, the shore power connector on the hull is severely corroded, and the PO was using an extension cord and a basic power strip in the quarter berth to apply that current, and it is totally NOT acceptable in terms of marine wiring to do that, I understand. I am going to hunt down a receptacle that is properly designed for that issue, and mount it in place of the corroded one (I really just need the electrical innards, the seal leaked and the cover and socket is there but the electrical part originally there has corroded away).

In the situation with the shore power wiring, what sort of wire is used for those loads within the marine environment? I understand it would be about the same gauge as that used for land based wiring so no problem there, but what sort of construction or insulation type would the wiring need? Would stranded wire be acceptable, and are there specific conditions apply that make stranded wire used non-marine applications unsuitable for routing my 110 circuits on a sailboat? Does the wire need to be tinned to use in marine even if the larger 110 v material? The runs of this wire will be shorter, perhaps 20 feet round trip, and potentially only broken into perhaps four or maybe five AC circuits, for reference.

The AC wiring will support a dorm fridge, the smallest microwave I can locate (and that same microwave outlet could be interchanged for use with a hot plate, so a single receptacle there), a 1500 BTU Air Conditioner, and some LED lamps (if I can locate them as 110, but if not, MAYBE some incandescents). I also have a small wall mount LED TV that the Admiral will surely want to use on occasion in port.

My 12v wiring will be for the previously mentioned lighting issues, plus I am considering using some sort of LED lighting for deck lighting and some temporary lights for while we are loitering someplace over a holiday weekend, for instance, rope lights, that sort of thing. I have some solar units I could use for that if pressed.

I have a 4000 watt inverter and a 3000 watt inverter available for use, and I want to use my depth finder, a laptop, gps, and cell when available service exists, as these help with navigation. I don't know what would be required for radar, but I am unsure that I would have resources to install that on this vessel anyway. I do have a working VHF, and will be adding a small stereo and some small speakers as well on the 12v circuits.

I looked for other threads with this sort of question in them, but though I seem to recall asking about something similar in the last year or so, I was unable to locate anything this diverse in the historical file (though surely someone has already chewed this fat already). If anyone can suggest potential ways to remedy problems they encountered doing this, I am definitely interested in learning from your issues rather than repeating them personally!