Oh, my, my! Reminds of a '67 E-Type I helped re-wire, once. About a third of the way through an attempted patch job, we gave up and just decided to do it all over from scratch. I still think we saved time in the long run.
While I would like to say that Wayne's right and maybe he is and you can
salvage some of it, you are about to start on a very long
cruise. Do you really want to have the nagging doubts 1000 nm's from anywhere? You know the ones, "bad wiring means high resistance, means heat, means..." In that light, I've got to agree with Bill.
Start with an inventory of every electrical consumer from bow to stern,
keel to masthead. Go, slowly, through the boat, noting the consumer, colors and gauges of wires, any intermediate junctions (oh, my god, I can just imagine the splices you'll find!), and bus bars. If at all possible, find out the
service requirements for each consumer. Don't be surprised to find undersized wire -- if it is, even if it looks good, you'll want to replace it.
Label the conduits (you do have conduits, yes?) (If you've got multiple conduits terminating together and it isn't obvious which is which, you can take a small blower -- like a hair dryer (NO HEAT) or
dinghy pump, tape it around one end and then when blowing go to the other end and feel for the air coming out.)
If you've got a CS schematic to compare your "as built" with, that might be a big help in starting an organizing plan for your new schematic. If you don't have one, then contact CS and see if they can scrape one up. This is like an archaeological dig, at some point you'll scrape away the trash and find the original plan. Having that schematic will help you recognize it.
By the way, this is a great time to do any upgrades you've been thinking about. Might as well factor them in, too.
You might as well just count on completely replacing your panel, breakers and bus bars. If they're original, you'll find the new stuff much more convenient and your breakers probably won't meet spec anymore, anyway.
Once you have (1) your
current inventory, (2) any additions you want to make, and (3) the underlying original schematic, then I'd highly recommend hiring a
marine electrician for a couple of hours to come aboard,
survey the situation, and then show you various tips and good practices to get you on your way. The advantage to this is he will be able to lay his eyes directly on your situation and give you specific advice and a recommended plan. Also, if you should run into a trouble spot you can't solve, you'll have a contact already familiar with your boat to help you through it.
Doing these jobs (I've personally done several cars and two boats) is really not all that technically challenging once you have developed good practices and have a well organized plan. Set yourself up some reasonable goals for a day's
work and work on circuits that are in the same general area of the boat. E.G., today we're doing
instruments. Tomorrow, forward
cabin and bow nav lights. The next day,
windlass. Write out your plan, with checklist of tasks and before you know it, you'll have it all done. A couple of buddies,
fish tape, pull strings (don't forget to always pull an extra one) and a discount at your favorite supplier will see you through it.
Don't be surprised to find that you have a lot of orphaned wires. Just pull 'em and get 'em off the boat. (You might even find that old 8-track somebody installed way back when!) If you leave them, they'll just confuse you and throw doubts your way when you least need them.
Do you have 110, too? Is that as bad?
Good luck, keep us posted.
ID