Battery Problems!!!

dwelch022

Seaman Apprentice
Joined
Jan 5, 2013
Messages
38
Hi guys. I recently pulled new cables through for a new fishfinder and 2 throttle/shift cables. Every since I pulled these cables through my wouldn't start. I sounds like it would when a battery is going dead when I turn the key. So I charged both batteries and still had the same problem. Next I saw that I have a two negative cables on the negative side of my battery. One coming from the engine one wire that splits of in two direction. The wire splits off to the trim tab power box and the other splits off to an unknown location toward the circuit breakers at the dash panel of my boat. The reason I'm saying all this is because when I disconnect the cable that splits in two the motor cranks right up. When I put it back on the battery it seem like it shorts out the battery preventing the motor from starting. The cable that splits in two runs the same route as the cables from the throttle and fishfinder. Before I ran the new wires everything was working perfectly. Sorry for the long post. Does anyone have any thoughts on this? I will include pics tomorrow if it would help!
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,799
Re: Battery Problems!!!

The negative cable is not shorting out, preventing the motor from starting.

The negative cable is completing the circuit for whatever is connected to it.
Something on that line is consuming power.

Pop the fuses or breakers, or disconnect the power going to...
the trim tab box and the dash power panel, then try to start the motor.

My guess is that the power going to the dash, is what is grounding out.

If it is drawing enough power to prevent starting, it is likely getting hot, possible arcing, and causing a fire hazard.
 

dwelch022

Seaman Apprentice
Joined
Jan 5, 2013
Messages
38
Re: Battery Problems!!!

Thanks I'll give it a try tomorrow. Also, I have a battery terminal cable connected to the negative of my main battery running to the negative of my second battery. I switch between batteries using a switch. The motor also fails to start with this cable connected now, but when I disconnect the cable it fires right up. This has never happened before. All other accessories work, I just can't seem to get enough juice to start the motor with these cables connected for some reason.
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,799
Re: Battery Problems!!!

Thanks I'll give it a try tomorrow. Also, I have a battery terminal cable connected to the negative of my main battery running to the negative of my second battery. I switch between batteries using a switch. The motor also fails to start with this cable connected now, but when I disconnect the cable it fires right up. This has never happened before. All other accessories work, I just can't seem to get enough juice to start the motor with these cables connected for some reason.

This leads me to think that one of your batteries has a bad cell. Although in theory, it should start with one dead battery, thats why we put in dual battery systems, right? But I have seen this happen twice.

I would remove them and take them in to have them load tested.
 

dwelch022

Seaman Apprentice
Joined
Jan 5, 2013
Messages
38
Re: Battery Problems!!!

This leads me to think that one of your batteries has a bad cell. Although in theory, it should start with one dead battery, thats why we put in dual battery systems, right? But I have seen this happen twice.

I would remove them and take them in to have them load tested.

I'll take them in tomorrow, both are still under warranty. If the batteries had a bad cell, should they have started the motor once I disconnected the other cables?
 
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