The MV ScubaBoard...

[Peter_C]

Except most relays are ground switched, then the relays controls the positive feed to the component.

Modern boat electronics tend to use circuit breakers not fuses too.

 

[DennisS]

There is a color code for wiring, although in older boats it's not uncommon to have a blue wire spliced on to a red wire because that's all he had.


Marine Color Codes | Marinco

Mercruiser 3.0L Wiring Diagram - Performance Product Technologies

 

[The Chairman]

A color code for wiring... how cool. I kind of like that. Thanks.

 

[Tom Winters]

The color codes make troubleshooting much less arduous when you have a problem. I looked at a couple of boats that had been wired and rewired with automotive wire from Billy Bob's Bait, Boat, & Barbecue that needed electrical repairs. I passed on 'em - easier to do a ripout and redo it correctly.
Even with properly colored wires, and there are a lot of different colors - what really helps a LOT are the Ancor write-on shrinkwrap electrical labels - you can write notes to yourself in the future when you're backtracking an electrical problem and everything in the little puka you wedged yourself into looks the same. Unbelievably helpful.

 

[LowVizWiz]

This is what needs to happen:

1. Thorough Cleaning
2. Deck Support
3. Complete Rewire with New Switches and Gauges
4. Install New Batteries
5. Drain Old Fuel
6. Rebuild Carburetor
7. Install New Plexiglas Windshield.
8. Figure out Throttle/Shift Linkage (probable rusted cables)
9. Buy/Install Electronics (Marine Radio and GPS/Depth Finder)
10. Find/Recover Anchor with Chain
11. Test-Test-Test
12. Buy Tow Boat USA

I am struggling with switching power or switching ground. There are good arguments for both. In a car, the ground is always at the device, but not so with a boat. Most of the devices are near the batteries, so running a ground from the back of the boat seems reasonable. I think I'll just keep the fuse box in the cockpit area (drier) and so will run a single #8 AWG wire to the cockpit from the battery switch. Its a ganged fuse block using 10 blade style fuses. The fuse block has a detachable ground gang as well utilizing spade connectors. I think I'll mount that in the stern area or possibly get one that uses screw down connections.

I see that I will need these circuits that I will run on #12 AWG:

• Engine Run (Breaker Point Ignition, electric fuel pump & Alternator)
• Engine Start
• Trim up
• Trim down
• Bilge Pump
• Running Lights
• Interior Lights
• Marine Radio & GPS/Depth Finder

I will also need these on #18 AWG

• Engine Oil Pressure Light
• Engine Oil Pressure Gauge
• Tachometer
• Voltmeter

With this much stuff to get you're going to need someone in charge of "SUPPLIES!!!"

I couldn't resist!

Good luck with the project.

 

[The Chairman]

With this much stuff to get you're going to need someone in charge of

Spoiler

SUPPLIES!!!

I couldn't resist!

Good luck with the project.

Too freakin' funny. You do have to learn how to use the [spoiler][/spoiler] tags.

 

[MXGratefulDiver]

You'll need a new avatar, Pete ... might I suggest ...

... Bob (Grateful Diver)

 

[ajtoady]

Pete, my suggestion would be use all MTW stranded copper wire. The insulation is thick and tough. For most of your controls a 14 or 16 gauge is more than enough and for your fuse block feeder, a 10 gauge would be sufficient. Another suggestion would be before cutting the old harness out, make yourself a schematic of what now exists and try to compare it to what it should be. If you need any drawings or schematics let me know and I can probably provide them. Invest in the proper tool for all of your wire termination connections and if possible, soldering is by far the best prevention against salt water corrosion on terminals. Labeling wires also is a help.

 

[Lobstah Slayah]

You'll need a new avatar, Pete ... might I suggest ...

... Bob (Grateful Diver)

He's been promoted, now that he owns a boat, he's Admiral Pete!

Here is a suggestion for his new Avatar...

 

[MXGratefulDiver]

Gotta change that C to an S though ...

... Bob (Grateful Diver)