Battery Draw Down

[WalleyeHunter1]

I took my boat out of storage today but stopped by last week and put the batteries in, and hooked them up...when I got there today and trimmed the motors they barely had enough juice to lift the motors. The key was off and the master power switch was off. Where do I start?

[Juls]

I'm no expert, but from my understanding, the motor will be drawing on the cranking battery even with the master switch off unless you specifically have a breaker between the motor and the battery.

I leave my charger plugged in all the time when the boat is on the trailer.

I'm sure I will be corrected if I am wrong...

Juls

[boat nut]

Originally Posted by Juls

I'm no expert, but from my understanding, the motor will be drawing on the cranking battery even with the master switch off unless you specifically have a breaker between the motor and the battery.

I leave my charger plugged in all the time when the boat is on the trailer.

I'm sure I will be corrected if I am wrong...

Juls

Juls is correct. The engine's computer can still draw current when the master switch is off. However, I disagree with leaving the batteries on a charger all winter (where I am, winter is just about over now). If you charger or a battery fails, you could have bigger troubles, the worst case scenario being a fire. I prefer to disconnect all fully charged batteries from everything (all cables removed) for winter storage. At low ambient temperatures, a fully charged battery can be stored for months, and only require a few minutes of charging in the spring.

[Juls]

Originally Posted by boat nut

However, I disagree with leaving the batteries on a charger all winter

He just put the batteries in, so he's not talking about keeping the charger plugging in all winter, but rather...right now.

During the fishing months, I leave it plugged in so that I know when I go out I have fully charged batteries for the day.

I never have a boat to worry about in the winter, so your advice is probably good for those that do. It just doesn't apply to me.

Juls

[nwpaconcours]

Pretty simple (but maybe tedious) matter to disconnect all the electronics and connect them one-by-one with even a cheap ammeter hooked to the battery and the respective lines out at the battery. It's easy with two people, and can let you diagnose vampires.

I had a used boat that the owner had gone through batteries every year. The radio/CD drew a surprising amount of current. Once the CD half of the radio was disconnected (then the whole radio switched) there was virtually no current draw on the battery in storage.

[Sparkyd]

The plug you had charger plugged into didn't shut off when you shut off the lights did it?
Don't ask why I would think of that..
Dave

[bridgeman]

Do you have a kicker with a trollmaster? It'll draw the battery down over the winter months