Really Confused Here, Please Help!!

jmw129

Petty Officer 1st Class
Joined
Jun 12, 2011
Messages
253
Hi guys,

I recently bought a boat that has a 1985 Mercruiser 4.3L and here are my problem(s)....

All of the wires to the engine that go the battery are all Black?

Why isn't positive red? I just couldn't believe what my eyes were seeing :eek:

Well I hooked everything up the way I though would work without firing or over surging the system... Well I noticed smoke coming from under my dash and when I checked my fuses I noticed none of them were tripped / split in the middle?? :confused:

The Trim gauage works but my battery voltage gauge does not show any voltage? I know the battery has a ton of juice so I know the voltage is there.

The lights on the panel don't light up?

My gas gauge does not read?

My engine does not crank? Turn the ingition key & nothing?

What do you think is going on? Bad starter? Ignition coil? Burnt relays?

I'm totally stressed with this problem.. Thanks for your help as I can really use some help with these problems listed above!! :confused:
 

chriscraft254

Commander
Joined
Jun 4, 2011
Messages
2,445
Re: Really Confused Here, Please Help!!

Ok, calm down. I don't have all the answers for you without seeing some pics of the wiring but rest assured that you will get your answers with a little patience and its not worth stressing over. The black wires from the motor to the battery may have been as simple as the guy before you couldn't find the right sized gauge wire in red at his local store.

You just need to know how things are hooked up and then you can take a red tape and mark the hot wire lead. Do you have a battery switch somewhere onboard? What kind of boat is this?
 

jmw129

Petty Officer 1st Class
Joined
Jun 12, 2011
Messages
253
Re: Really Confused Here, Please Help!!

The boat is 1983 Mark Twain Sonic 175 with a 1985 4.3L V6 Mercruiser
 

Boater Bill

Cadet
Joined
Aug 11, 2008
Messages
16
Re: Really Confused Here, Please Help!!

my wiring harness from my block (which included the starter relays) had a lot of bad connections on my boat when i redid it. That MIGHT be part of the issue... pull it out and see if the prongs are in tact and that they are in good connection with the wires inside the harness - a good visual check works good.
best of luck!
 
Joined
Mar 27, 2010
Messages
3,008
Re: Really Confused Here, Please Help!!

That's what happens when someone replaces wires with the wrong colors.

You can wrap some red electrical tape around the positive wire near the cable so you'll know down the road. Hopefully it is contained to the battery cables and not other wiring on the boat.

You might want to invest in a test light or Digital Multi Meter, so you can actually check where you do and don't have power.
 

jmw129

Petty Officer 1st Class
Joined
Jun 12, 2011
Messages
253
Re: Really Confused Here, Please Help!!

So if I buy a Digital Multi Meter which setting works best to test the power source?
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,149
Re: Really Confused Here, Please Help!!

So if I buy a Digital Multi Meter which setting works best to test the power source?

Ayuh,... the 1 that reads 12v, DC...
 

NetDoc

Chief Petty Officer
Joined
Aug 20, 2011
Messages
517
Re: Really Confused Here, Please Help!!

Unlike their analog counterparts, DVOMs (Digital Volt Ohm Meters) normally do not have selectable ranges (auto-ranging). In fact, DC may be indicated by a straight solid line over a straight dash line. AC is often portrayed as part of a sine wave. To speed things up, clip the common (ground) lead to the engine.

The best way to sort wiring out, is to be methodical. Physically trace each wire, one by one. Do not go to another wire until you have the origin and destination figured out. This will take some patience and time, but its important to take your time and do it right. This is a time where slow is actually fast.
 

joewithaboat

Lieutenant Junior Grade
Joined
Jul 3, 2011
Messages
1,172
Re: Really Confused Here, Please Help!!

Not sure if this would apply to your situation. I bought a boat last year that was stored on a lift, on the water. more than half the gauges didnt work. I guess being near the moisture all the time is hard on the gauge connections. In my case nothing was wrong with the gauge or wiring, simply had to wiggle the push pull spade type connectors and or loosen and re-clock the nut/post connectors and make sure everything was tight. Good luck patience is your friend.
 

Grandad

Lieutenant Commander
Joined
Jun 7, 2011
Messages
1,504
Re: Really Confused Here, Please Help!!

NetDoc has it right. Physically trace the wires. As tedious as that might be, it's the best way in the end, especially if electrical troubleshooting is not your specialty. Start with a pencil and a big sheet of paper. Place marks for all the significant electrical components and identify them. It helps to arrange the component marks on a top view sketch of your boat from the fat end to the pointy end. Once you have this diagram, it should become evident where each wire belongs. Put name tags on each wire as you identify them, using masking tape if necessary.

Once you've found and fixed the problem(s), you can properly identify the wires with color tags or replace them entirely as you see fit. Now take your sketch and redraw it more neatly and save it for posterity, maybe even computer scan and save the document. You can print and laminate a copy to store in the boat's glove compartment for that day out on the water when your bilge pump blows a fuse or your lights don't work. - Grandad
 

jmw129

Petty Officer 1st Class
Joined
Jun 12, 2011
Messages
253
Re: Really Confused Here, Please Help!!

Great advice everyone. Having to trace these wires down seems like a pain. Worried about surging the system or firing components if I have the negative & positive crossed which I think I did once already.

Is there any reset buttons any where that would stop the current flow?
 
Joined
Sep 29, 2011
Messages
17
Re: Really Confused Here, Please Help!!

If you can find the starter then trace back the cables, 1 to ground and 1 (should be red) to the battery.
Make sure these are correct before starting or turning on accessories.
You may have extra thinner wires connected to the posts of the battery, these are some of you accessories,etc.
 

Bondo

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Apr 17, 2002
Messages
71,149
Re: Really Confused Here, Please Help!!

Great advice everyone. Having to trace these wires down seems like a pain. Worried about surging the system or firing components if I have the negative & positive crossed which I think I did once already.

Is there any reset buttons any where that would stop the current flow?

Ayuh,... It sounds like yer in Way over yer head,...

Yes, originally there was a circuit breaker on the motor,...
Donno 'bout now...
 

Fishermark

Vice Admiral
Joined
Oct 19, 2003
Messages
5,617
Re: Really Confused Here, Please Help!!

The smoke suggests something melted / tripped. You may have a big circuit breaker with a reset button on your engine somewhere. You may even have a fuse on the starter. It will look like a big 1 inch square box that the battery cable attaches to.
 

jmw129

Petty Officer 1st Class
Joined
Jun 12, 2011
Messages
253
Re: Really Confused Here, Please Help!!

Hey guys,

I found the problem. All of my cables are black as stated in my original posting. I found there are two 50 amp fuses right on the top of the engine hidden in black rubber connecting tubes that are reinforced with metal pins that wrap around to ensure they stay covered & together.

After replacing the 50 amp fuse, hooked up the cable from the back of the starter to the positive terminal, the other cable on the back of the engine to the negative terminal and the other black cable (thin) running from the dash to the back of the engine to the negative terminal, everything read on the gauge as should.

Took a long time for the engine to actaully fully run but did crank numerous times without blowing any fuses or smoking any wires in the process.

I believe the problem has been fixed or at least enough to ensure the engine will probably run as intended. I'm just amazed how smoke that came from under my dash didn't fry the wires but I'm sure there is melted plastic or rubber left behind.

I can't believe that people don't use red & black wires. Just seems like common sense to me but then again this is the real world. The negative cables are NOW marked so I know which is negative and the positive black cable is marked with red tape.

I hope my experience can be a helpful learning experience for anyone else that has experienced this problem or currently experiencing it.

Be prepared to have 1-5 spare 50 amp fuses available as you may blow them all before finally figuring out the problem. Luckily for me the previous owner was nice enough to text me back letting me know what he thought was the correct connection and luckily his memory served correct.

Be alot easier if you had someone there to watch your gauges & for smoke so you don't leave your connections on too long and really mess-up with your wiring. Even with the fuse blown I noticed the wires still got hot & smoked behind the dash so be quick, alert, and don't waste time because they heat-up fast.

Thank you for all your help everyone! Sounds like a lot of you guys based on your replys may have been there yourself.
 
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