Help- 2021 Bennington battery keeps draining

[Malecha]

I need help! We got our boat last summer and towards the end the battery would die. We have 3 batteries as we have a trolling motor, sea legs and electrical.
The problem is it wasn't always consistent on what wouldn't start. Sometimes the engine wouldn't turn over and then we would use the on board charger and the next time the sea legs wouldn't go down.
Had it up and running yesterday and the radio worked, the sea legs went down but engine was dead.
How do we know what battery runs what on the boat?
Also, any idea's what is going on? We have made sure everything is turned off but wondering if something is still draining it?

Thanks for your help, so frustrating!!

 

[Vikingstaff]

I need help! We got our boat last summer and towards the end the battery would die. We have 3 batteries as we have a trolling motor, sea legs and electrical.
The problem is it wasn't always consistent on what wouldn't start. Sometimes the engine wouldn't turn over and then we would use the on board charger and the next time the sea legs wouldn't go down.
Had it up and running yesterday and the radio worked, the sea legs went down but engine was dead.
How do we know what battery runs what on the boat?
Also, any idea's what is going on? We have made sure everything is turned off but wondering if something is still draining it?

Thanks for your help, so frustrating!!

Well…you have a lot going on there. I think typically the trolling battery is often separate from hook up with others.

Do you have a dual battery with perko swithc set up…and then added a 3rd battery aftermarket for trolling motor? OR did you just have a single battery, and over time added the extra two on your own? Can you explain and/or provide pictures of your set up?

I will speak to this part only from a knowledgeable perspective: The Sea Legs. I have them. Did a lot of research and inquiry before and since getting them. Some of that due to nuances of having them.

Our set up: Dual batteries from factory build with perko switch.

Regardless of set up, Sea Legs draws a very low amount of power from your system all the time. They are a direct connect item. They also have a minimum voltage of 12.2 volts to operate. If your battery is below that, they will not operate so as to leave you cranking power for motor (which is ironic since if it is up on the Sea Legs, you cannot start your motor because its out of the water…anyway…).

So…if you boat sits for awhile, AND if your batteries are all interconnected, the sea legs can draw down on them. If they sit for 3-4+ weeks, this can and often will happen. In theory having your perko switch turned off (for dual battery set up) will protect battery power, but Sea Legs hook up bypasses this on whichever battery it is connected to. Typically Sea Legs installation is to non-cranking battery, or battery #2 in dual battery configuration with perko switch.

Secrete to stopping this low parasitic draw from Sea Legs: Locate your Sea Legs circuits breaker on your line. It is on the postive connection line. Box, with blue button and yellow switch. It looks like this:



Trip the circuit breaker on that box to cut off power to sea legs when boat will be docked and not used. You’ll have to reset it the next time you go to use your boat, but it will prevent the slow power draw.

And that my friend is at least the solution to the potential Sea Legs portion of your problem.

 

[Vikingstaff]

Separate FYI…below are pictures of battery #2 in my dual battery set up. It is the one the Sea Legs are connected to. I am providing these pictures for reference to you in how yours may or may not be hooked up. Not sure if it will be helpful or not.