battery drain

[Denis Sears]

Good day,
I have 1980 silverline, merc 140 inboard. My problem is that something is draining/killing the battery. I can place a newly charged battery in the boat and sometimes it will run for hours/several trips and other times it just draws the power and kills the battery. The +/red cable gets very hot with the instant discharge. My resistance wire from the coil is kringled and warm, could this be my problem and will a new coil fix it or am I still looking for that needle in a haystack.
Regards

 

[Bt Doctur]

Re: battery drain

the heavy red battery cable goes to the starter , boat power comes off a 10Ga wire ,doubtful it is system related to get the main battery cable that hot. What is the voltage gauge reading? Resistance wire usually does get warm,

 

[alldodge]

Re: battery drain

Sounding like the ignition is being left on even though the key switch is off. Start removing any extra connections on the battery terminals and measure the voltage as BT stated. Then let us know what you find