1979 Bomber Cobra wiring questions (Mercury outboard)

79bomber

Cadet
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Jul 5, 2015
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In my rear fuel tank area, there are 4 wires that seem to all be in the same harness. There colors are red w/ fuse, blue, black and white. The red w/ fuse and blue wires have connection ends on them, but they are folded and taped together and not hooked to anything. Does anyone know what these wires are supposed to be used for?

Also, there are 4 other wires coming from my Mercury Deluxe Ignition Comtrol (1979) harness (white w/ purple stripe, white, brown and black). The white w/ purple stripe and solid white wires are not hooked up at all either and they have connections on the ends? What are these wires for?
 

Chris1956

Supreme Mariner
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Mar 25, 2004
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What harness do the first set of wires belong to? If it is the boat harness, I am not sure where you can get the info.

Since 1979 was a switch-over year for wire colors, they may be non-standard. The Merc Ign control wires look to be for the power trim gauge(white/purple), and perhaps an overheat warning(brown). Black is likely ground. Not sure what white is, although old wiring color white was ign accessory power.

Hope it helps..
 

GA_Boater

Honorary Moderator Emeritus
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May 24, 2011
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49,038
I guess you could start by finding out if some things don't work. Old Merc harnesses like to fall apart over time and it's possible the prior owner did some wire replacement and left the old taped wires in place.
 

79bomber

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Jul 5, 2015
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I am attempting to determine if there is a need to have any of the wires connected that are presently disconnected (all wires mentioned in original post). There has been vast re-wiring in the past and some wires may be changed.

The ones I mentioned are believed to all be factory. I am going to attempt to see if the wires have continuity and go from there. I'll report soon.
 

79bomber

Cadet
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Jul 5, 2015
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27
The 4-wire harness that runs from the front to the rear feeds the trolling motor plug, trim control switch, volt gauge and a Run/Charge switch (red w/ fuse, blue, black, white)

I see no reason for the red w/ fuse wire and blue wire to not be hooked up. The front gauge light didn't work on the boat, but it worked when I tested it off the boat. There are no inside courtesy lights working on the same side this harness is on. Could the blue wire fix this?
 
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