No announcement yet.

Question: Battery Drain-gctid391354

  • Filter
  • Time
  • Show
Clear All
new posts

    Question: Battery Drain-gctid391354

    Hail all!

    My 245 SB is usually in a state between being in the water connected to power or in a large local warehouse for storage (the kind where I can call them up and have it dropped in for use). The problem I have is that my battery's drain after about 1-2 months from being disconnected from power. What happens is I have the guys drop my boat in and the battery is dead and they have to jump start it for me (they have been good about this). Now, I set my battery bank off yet something still draws power and I have no idea how to fix this. I know for sure that my CO2 detector stays on because when the battery gets low, it starts beeping. I'm wondering if this is the only thing causing the problem and how to get around it. I wish there was a fuse I could pull when it goes into storage like that to take draw off the battery. It's very hard to do much more since I dock the boat, they get in it, fire it up and put it up on their lift to get it back into the warehouse (so I can't say disconnect the battery myself). Thx for the answers! With the $1200 I just had to fork out for a water leak through my bellows that cause rusting of the shafts and barring, I want to keep my boat in the warehouse permanently so this becomes more of an issue.

    that's one of the problems with trailer boats parked for some time. You really want a master switch where everything gets turned off but that's against having the detectors and bilge pump(s) hot wired.

    Solution 1 (my current one): remove the + cable from the battery when I store it for more than a week.

    Solution 2 (on last boat): a power switch in the + line directly at the battery. I had a switch which needed a key to activate/deactivate and it was keyed like my ignition switch. Unfortunately the company which made this switch no longer makes them.

    One problem you have with regular batteries is that they have a rather high self discharge rate. Just look at your car. If you park it for 2-3 months the battery will discharge almost to the point where it doesn't start any more. If the battery is a bit older it will be empty. This is also bad for starter batteries as they die fast if discharged deeply. Deep cycles are a bit more forgiving but it hurts them too. They only have a larger gap at the bottom to accumulate the fall out from the plates. No miracle technology........

    The current drain of your detector and eventually some other electronics (modern radios and VHF's usually draw some current in off position!) you just make the discharge a bit faster.

    An AGM battery like the Optima or others (Optima is just one option) is a lot better there but everything should be disconnected there too.


      Solution 3 - Move the CO detector wire from the "always on" terminal to the switched terminal on the MBSS.

      This came up once before, and at the risk of another batch of popcorn, the consensus I believe was that I'm never in the boat to be exposed to CO when the batteries are off. Obviously if you can't make that statement a 100% guarantee, then you don't want to go this route.

      I had the exact same issue, turned the MBSS off in the fall while getting the boat ready for winter, and after a few weeks the CO alarm was beeping because of low voltage. Now that it's wired after the switch, I can leave the whole thing hooked up all winter with no problems (although I do top off the charge every month or so.)


        true, and on a small boat the only vapor you have to fear is from the fuel and battery and there's no way you can start the engine with the power off. It's basically what I had with my setup, one switch to completely disconnect everything, even the bilge pumps, as this was the trailer position only.


          You can go with the battery disconnect for the first step. When you are down there, look for how many "hanger-on wires" there are. These are power wires that somebody may have added that run directly off your battery. They can draw on your battery, are a hassle to put back on, and can be overlooked when hooking up the battery terminals. If some of those can be moved to your MBSS switch, then I would.