Drain on my main boat motor battery

[wiperhunter2]

I tried earlier this week to disconnect the negative wires going to the battery, then I connected them one at a time. I expected to see a spark from the wire drawing the voltage but none of them sparked when I touched them back to the battery. I'm going to try the positive side next to see what happens. Once I figure out which wire is drawing the voltage, it should be an easy matter to tell what they go to. I'll just leave it disconnected and see what doesn't work.
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