what does this wire do

[dogdoc]

finished the transom/bilge redo. New batteries, neg buss, 6 circuit pos fuse panel, 3 new battery switches, new float switch and a general good clean up. Looks and works fine. Question is a 10 gauge wire which was a direct battery connection with a large 20-30 amp inline fuse (so corroded could not read clearly). This looked factory as it runs in the chase in the bilge with the other wires, but I cannot find it on a wiring diagram or trace it out. Any ideas?

 

[Tuna Man]

Couple of ideas. Could be designated wire for VHF radio, could be for a second (or third) small fuse panel that would supply your electronics?

 

[DennisG01]

What year boat? Have you had it since new? A previous owner could easily have fished it through the chase.

10g is big enough that it could be a feed to a fuse panel. But it should go through a battery switch... making me think it might be something installed by a previous owner. The only things that are typically installed direct are things like float switches and stereo memory. A bow thruster might be installed direct - but usually the battery is installed close to the thruster to avoid running a large gauge wire (which I think would be larger than 10g, anyways).

What doesn't work if you remove it?

 

[seasick]

It could be part of an aftermarket installation. I doubt is is radio related, more likely related to trim tabs, windlass or some other high current accessory.It could be related to a battery charger also.

 

[Bfrench7]

What color is the wire?

 

[dogdoc]

sorry working on boat and prepping for dorian at the same time. It is a 92 model grady 280 marlin twin 250 yamaha 2 strokes. the wire in question is red 10 gauge and seems to go through factory chases, was fused fairly big 20-30 could not read fuse because of corrosion. Seems to go to helm some place when storm is over may try a continuity check and see what i can find

 

[DennisG01]

OK, at nearly 30 years old, it's probably hard to try and guess what is factory and what has been done by a previous owner. As noted previously, just going through a factory chase doesn't mean it was run through there at the factory - it could have been , but a previous owner could easily have done it. You can download your manual and look at wiring diagrams - or, like I mentioned, just remove it and see what doesn't work. A continuity check is good, too.

Good luck with Dorian - hope you fare well.

 

[dogdoc]

Yea I see Bubbas tracks all over this boat. Why do people just leave cut wires hanging around to confuse those down the road rather than cleaning up as you go.

 

[dogdoc]

Got some good work done today in spite of Dorian. Cleaned up all unknown wires except that red 10 ga from the stern. Seems like it is going to the helm switch panel but still not 100 %. New question is the dc 50 amp breaker at bulk head ac/dc panel . Seems to me that should be the main and protect all other dc breakers in panel and allow disconnecting power to those breakers. The way it is wired is power coming to line side and output on load side. Load side is connected to branch circuits via a copper bus bar. In that manner it does provide power to the breakers and acts a switch to disconnect power to the branch breakers but does it provide overload protection. I was always taught that wiring a breaker backwards eliminates overload protection downstream. My thought is to cut the bus bar after the main and then wire correctly.
Would like others opinions

 

[dogdoc]

Red wire turned out to be an aftermarket spotlight which did not work at the light but did have tiny indicator lights at the directional switch on the helm that I only noticed when working on the boat in the dark with a head lamp, pulled the fuse and the indicators went out. Will dc the light but now have a open 10ga 12 v wire going to the helm to put into use. The dc main circuit breaker can be wired in either direction to provide over current protection unless it has polarity indication, ie + and - markings. This does not

 

[SkunkBoat]

Did you ever find a 10 gauge black return wire for that? or did he use the existing ground bus under the dash?

If you have both sides, you could parallel them with the 6 gauge House wires to the bus bars and it would be like increasing the wire gauge. It would reduce the voltage drop across the feed wires.