Mercruiser 140 Battery Drain

[bjarnold1]

I have a 1984 Seaswirl with a 140hp Mercruiser 140 4 cylinder and after setting for 3 days the battery is dead. I installed a new Napa deep cycle marine battery right after I bought the boat a couple of months ago. When I turn the key to the on postion without starting it the tach jumps to 5K and the instruments work but the trim motor, ignition, they do not operate. What could the problem be?

 

[Redneck Yacht Club]

Re: Mercruiser 140 Battery Drain

Why are you using a deepcycle battery to crank your motor?
2 ways ya can fix the battery drain problem, get a muiltmeter and test for amps draw on boat side main power wire. Second is to install a main battery ON/OFF switch.
As for the other stuff not working now, am guessing ya missed some grounds wires on the battery or bad conection at the ground block.