Good Lord, what a mess.

[NMShooter]

What is it about boats that induces the most simple minded people to believe that they are Thomas Edison?

I'm trying to add a fish finder to my "new" (1988 Bluefin) boat. I crawled under the dash and couldn't believe what I saw. Wires snaked everywhere. A dangling terminal block. Cut wires, hanging connectors, oxidized electrical tape. What a mess.

(I know what you're thinking... "If you are such a genious yourself, why didn't you check under the dash before you bought it?". Okay... you got me.)

But at least I know better than to play with road flares and gasoline, I never run with a fork in my mouth, and all my power wires always have an inline fuse very, very close to the power source.

So here's a couple of questions for you.

1) It seems to me, that many of the electrics on the boat should be capable of having power, even if the key is out of the ignition switch. Things like the bilge pump, nav lights, fish finder, radio. Am I crazy?

Right now, my entire electrical system is dead unless the key is in the "on" position. Being a new boat owner, I don't know enough to know better.

2) Any damage being done to the engine electrical system (1988 Force 85hp) if the key is "on" but the engine is not running?

3) Why would my voltmeter need three wires going to it? Do some systems not turn on the illumination unless the running lights are on?

Sigh. Looks like winter of 2010 will be upholstery AND electrical.

Thanks for any insight. I'm heading back out to my boat to see if I can scrape the small remaining amount of flesh off of my knuckles.

 

[Barnacle_Bill]

Re: Good Lord, what a mess.

Sometimes its easier to tear everything out and start over.
1- True not all things need to go thru the ignition switch.
2.-Shouldn't be except for running the battery down.
3.-One for ground, one for power (usually the ignition switch), and one for the light from the lights switch.

 

[stylesabu]

Re: Good Lord, what a mess.

I would definitly put another switch in place for accessaries. easiest would be to replace ignition switch but if it part of boat controls that may be a lilltle harder. I wired mine so that what is needed when running runs off ignition switch(tach, volt meter,fuel gauge, oil gauge) everything else has a switch/or is switched off a main 30 amp switch. put some time into how you want things to work and solder and shrink wrap all connections and do each curcuit one at a time. it looks worse than it is cause somebody didn't take the time to do it right. I know just redid mine the old guy I bought it from knew just enough to make things work, but not how to do it right. he used a lot of scotch locks and twisted and taped connection. The first day i took it out most of the stuff on the dash flickered, and would quit. i shoul;d have saved those pictures

 

[Silvertip]

Re: Good Lord, what a mess.

In 1983 the boat manufacturer probably hired a high school drop out that had one semester of industrial arts as their "electrical guru" because he proved he could actually install a new plug on a power cord. Consequently boat wiring for decades was a nightmare for anyone trying to troubleshoot an issue. In the real world, boats have two electrical systems. The harness that runs from the engine to the ignition switch and control box carries +12 volts to power the gauges. and sometimes some very low current draw accessories. This line did not power the fuse panel. The fuse panel got power from the battery directly via two #10 gauge or similar sized wires. The accessories were then powered from the fuse panel. The ignition switch was not intended to carry high current hence the separate circuits.

 

[stylesabu]

Re: Good Lord, what a mess.

what i did to use my ignition power to power my dash was a 30 amp relay, similar to what you would use for driving/fog light on a car. I still run the 2 power wires as silvertip stated but relay is installed between positive 10 gauge wire and is triggered by ign. switch. now I'm using very little of engine harness current to turn on the rest of my boat, I also have a 30 amp on off switch to power boat with key off.

 

[Silvertip]

Re: Good Lord, what a mess.

But then ignition switch must be in the RUN position to power any accessory! This is a very bad design technique on an I/O or any battery ignition system since the ignition points or electronics would be powered even though the engine is not running. That burns up ignition points. There is no need for a relay. If you are forgetful, install a master power switch. Simpler and many fewer points of failure.

 

[stylesabu]

Re: Good Lord, what a mess.

no, the switch is wired to the switched side of relay. so no I'm not back feeding the motor.

 

[Silvertip]

Re: Good Lord, what a mess.

Look -- you need to have the ignition switch ON in order to activate the relay. The fact that the switch is on means the ignition system is also powered just like it would be if the engine was running. Obviously you are not back feeding the engine but if the ignition system is a battery ignition (as in points or electronic ignition) as most I/O's are, the ignition system is powered in the RUN position. Therefor if the engine stops with points closed you run the risk of burning them. If the ignition switch has an ACCESSORY position then that position does not power the ignition. Again -- this applies primarily to battery ignition systems. I just don't want folks to think they can do what you are suggesting on any engine.

 

[stylesabu]

Re: Good Lord, what a mess.

silvertip, I understand what your saying. But I have an outboard motor, I do'nt have an accessory postion on my ign switch. so I use a 30 amp switch in place of the relay, as my acc switch. i wish I had power point so I could show you better. this way i can use accessories in either postion. he ignition switch is just activating relay. power is coming from battery not engine harness