Additional Electrical Circuit

Germanmattlanta

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Gulfstream
I am considering running new positive and negative wires to a new fuse box under the helm. The boat is a 1994 Gulfstream with original wiring. Everything is working as it should but I am thinking to connect all new electronics GPS, Fusion Head Unit, NMEA, LED lights, VHF to a new circuit to not test the old wiring.

Does this make sense of am I wasting money? Also, if I run the new wires could I just add them to the battery switch? What gauge wire would you recommend?

I'll be running 1 gauge for amplifiers soon anyway and I figured it would be easy to add these wires.
 
There is not enough information to answer your question on wire gauge.
I also do not understand the amplifier needs and wiring.

What electronic loads do you have now and what loads will be added as opposed to 'upgraded'?
Running new wiring can be quite tricky especially for the negative feed for the existing or new fuse block

How are your current batteries configured?
How do you use the boat? For example do you sit/anchor for long periods of time with the motors off and that sound system scaring off the barnacles?
 
Do you "need" to upgrade the wiring... hard to say. But there's certainly worse things you can do than to upgrade 30+ year old wiring :)

Unless you're increasing the amp draw on the main dash power lead, there's no reason to upsize it (although it can never hurt to do that). Chances are, all of the "new" stuff you may get to replace the old stuff will use LESS power. You'll need to check your power draw and figure out what's best.

I'm not sure how your boat is wired, but ideally the main lead to the dash would come off the battery switch. It's best to avoid putting things right to the battery. This includes the ground - instead, best practice is to run a heavy wire to a negative bus bar and then use that for grounds.
 
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Does this make sense of am I wasting money?
I don't think that you waste money at all, 30+ year old cables can lead to a bunch of problems what may lead to no start conditions, so i would do it and include all other wiring.
I overhauled many boats and what i saw steers me to rather rip out everything and redo it than fixing one by one and running in to problems in between.
But be advised that replacing cables is trickier than many expect and you should buy the correct quality tools for that job.
Chris
 
I overhauled many boats and what i saw steers me to rather rip out everything and redo it than fixing one by one and running in to problems in between.
100% agree with that!

One little "mostly" broken wire inside a connector that you can't see makes for a big headache. Mostly broken is worse than fully broken!
 
Thank you for the input! Everything is working well so far. I think for now I'll wire everything to the original fuse block. DennisG01 you have a good point that the new accessories will draw less power. Eventually I will probably replace all wiring at once as Sardinia306 suggested.
 
The boat is 30 years old. Probably a good idea to replace everything electrical as you will be chasing electrical gremlins from the start. Especially if the boat has been kept in saltwater. If not then it may be good idea to run new main wires to a new fuse block or bus and hook up your new electronics and critical electric devices to these. You can replace other things like cabin lights and such as you go. Its a 23ft boat so there should not be a lot of electrical stuff to go through.