melted wire going to indash voltage meter

hey folks, over the weekend i was outside and smelled something burning. well i looked over at my boat and there was smoke going everywhere from under the back deck. that is where one battery is, and also the fuels tank, so you can about imagine how quick i was trying to get the battery cables unhooked.to make a long story short, after the smoke cleared i notice a wire coming from the negative terminal was burnt up. i got to tracing it and it goes all the way to the dash, and hooks onto the volt meter in the dash. everything in the dash is working, including the volt meter and the light in it. all of my pumps work.anyone have any idea what the wire may be used for? there are three wires total going to the guage.


thanks

Re: melted wire going to indash voltage meter

If you don't have a breaker or fuse on your battery + connection you have a chance of a serious meltdown and fire. Something is shorted or drawing too much current. It sounds like the previous owner was using the volt meter terminal as a - buss conection. SILVERTIP has very nice wire diagrams for most boats.

Re: melted wire going to indash voltage meter

hi star, this is the 3rd time i have owned this boat, i bough ti back in the fall after 2 other people having owned it.the wire that melted goes only to the volt guage in the dash and nothing else. and the volt guage is wired so that it only comes on if the main power switch is in the on position, it was wired like this from the factory. the guage still has the factory wiring plug connected to the back. the post that this wire is attached 2 has only this wire on it. the best i could tell last night, the guage gas three wires to it, 2 thru the plug and 1 coming from somwhere else. what is strange is that while i was trying to unhook the battery, i noticed that some of my red power on lights in my switches were lit up, even though the switches were in the off position. i am not sure why this boat need that ground wire anyhow, seein how everything is working with it unhooked from the battery.

Re: melted wire going to indash voltage meter

A picture of the back side of the guage might help diagnosing the problem.

Re: melted wire going to indash voltage meter

i will try to get one this afternoon, last night i was folded up under the dash with a dying flashlight trying to see what i could. LOL i will pull the guage out.

Re: melted wire going to indash voltage meter

from what you have said i would look at the insulation bushing that stops the positive bolt on the back of the voltmeter making contact with the bracket that holds the voltmeter (or any other gauge). As they get old the bushing wears or cracks and the positive bolt makes contact with the bracket. If the dash is metal that makes the dash positive and all the little lights start to glow. Then the positive finds a ground which could be the same gauge or another one as they are all connected and the smaller wire melts first. If its not the bushing then check the steering cable is not loose as thats another favorite for hitting the backs of the gauges. Ever wire thats connected to the battery post should be fused or have a breaker with in 6 inches (cheap in line fuse from autoparts are a few bucks each)

Glad you caught it early before it did any real damadge

Re: melted wire going to indash voltage meter

ok here is the latest update. i checked the guage and there wasnt any contact at all. the steering cable is out of the way also heres the really weird part. i ran a temporary ground wire from the battery to the main harness on my wiring harness under the dash. with it hooked up and my main power switch on, both i can turn on either th bilge pump, or the aerator pump, and both switches light up even if one of them is turned off, i checked my wires running to the bilge pump and i have 12 volts running through the ground and the positve wire .

Re: melted wire going to indash voltage meter

when you have 12v on the ground (dc negative) wire that means theres a break in the ground wire. Depending on the boat you may have a negative buss that is no longer attached to the battery. As a bonus if you have one small wire thats connected directly to the battery and you loss the main negative return wire all of the amps used will try to return on the wire thats directy connected.
All the black wires are normally nested on a bolt or a buss. try to find that connection point then check the larger cable that goes to the battery.

P.s if the boat was not in use and everything was turned off make sure you fuse any positive wires from the battery to the dash as something had to be on to complete a circuit (or there was a short) which overloaded the ground wire causing the heat and smoke
Do you have a auto bilge pump and is it fused?

Re: melted wire going to indash voltage meter

ok here we go , i had diagnosed a bad ground before i read your last post. the ground wire from the dash ran to the back under the deck and then was bunched up into a big crimp connector from the factory. i cut it all loose, and ran one ground from the battery to the back to run the bilge, aerator and stern light. then i am running another ground from the battery to the dash for the guages and the front light. i am leaving the cables unhooked until i can pick up some fuse links tomorrow and get them installed.while i was wadded up under the dash, i went ahead and got the non working lights going on the rest of my guages. i tell you it is tough for a 300 plus pound guy to find room to get under the dash on a 15x48 aluminum bassboat. especially while my wife is singing a rousing edition of fat man in a little boat. LOL

Re: melted wire going to indash voltage meter

got to love a wife that gives moral surport :lol: