Battery draw…boat question

[bigv]

So my cranking battery has been drained dead 2x now. Brand new battery too. It’s never had a draw before so just out of blue last two times. I have a kill switch for my 3 graphs, the master switch in dash kills live well, bilge etc. only other hook ups are kicker motor and 3 bank charger. I put boat away…dont use for 3 weeks (been wader fishing), plug in charger over night here and there. Then take out this morning and deep cycles good, crank …stone dead. Cannot find draw and has never had one. In researching, I think it’s a bad 3 bank charger?? I read a diode can go bad and reverse draw when not charging?? I’m going to put a new kill switch (big boy) on the main motor cable to kill whole boat but in the mean time….do you wiring/electrical/battery guys think I’m on to something??

 

[xFishSlayerx]

Sometimes you just get a shit battery right outta the store brand new. Things to ponder.

 

[bigv]

Well I wasn’t clear….first time was old battery. Figured battery cuz it was 5 yrs old. So put this new one in….happened again

 

[Rowdie]

I heard GPS puck constantly draws...??

 

[Rowdie]

If I don't go out for a few weeks I have to charge cranking battery, even when I bought it new.

 

[NDSportsman]

I think you're on to something with the charger issue. Disconnect your main from the charger and see if it still goes dead.

 

[wslayer]

Brothers boat up at Devils Lake was doing same thing, main switch shut off and still drained. I put battery disconnect switch on and hasn't had a problem last 2 years.
https://www.ebay.com/itm/2058610381...R8/sbyrgQvaMxupXuTUvCcHlgw==|tkp:BFBM5qfEu81n

 

[1lessdog]

I was always under the assumption that battery disconnect should be on the ground side. Maybe it's a thing, I don't know.

Brothers boat up at Devils Lake was doing same thing, main switch shut off and still drained. I put battery disconnect switch on and hasn't had a problem last 2 years.
https://www.ebay.com/itm/205861038158?_skw=battery+disconnect+switch&itmmeta=01KSNVH2F4XR98XFW8RAM5PR3A&hash=item2fee46284e:g:cR8AAeSwVJVp4vm5&itmprp=enc:AQALAAAA8GfYFPkwiKCW4ZNSs2u11xAaeQV2wNUGNPcWXgtOPUPdwIfO5PObjuxmH3na5C8YGfDVHBFCObZoMu/I344EMjM6C/6H6HulPL4squeRbDhY+4Fz3OktF0I7DF8hWwG5yLZdvBsIkbZTgqC90yGY2RJmRds4eyZL/LXhb1NheNP3VxEmLv9J/nzygi4Ez6dm3IOEB3sfKs8Z0u5hUuyESXdb/FXEork+3BTl7OaO4QI68C6Mo6QjG1lvCzsnryZXOXi/mHEhEJWdRyt3H+pHd+iGOGBcDd0xaYxKD1xoR8/sbyrgQvaMxupXuTUvCcHlgw==|tkp:BFBM5qfEu81n

 

[bigv]

Well after messing around, battery is shot. New too! Charges it up and watches with a meter tick down in no time. Bad battery like said??? But still, I still think charger is issue. Have read chargers cause issues…guys think batteries are problem when really it’s the chargers. I’m still at a loss. Going to replace battery again…hope get refund… then put big shut off on main cable to kill all.

 

[Slappy]

Plug in the charger with all batteries connected and check voltage with multimeter at each battery. If you're not seeing at least 14V that would suggest charger issue.

 

[Davy Crockett]

I was always under the assumption that battery disconnect should be on the ground side. Maybe it's a thing, I don't know.

That is 100% correct.

 

[bigv]

Now days I guess they put them in the main big motor cable then hook every cable to that one cable with lever shut off. Basically like taking every cable off off post…killing everything

 

[wslayer]

I was always under the assumption that battery disconnect should be on the ground side. Maybe it's a thing, I don't know.

Yes, this can be applied to side of choice.

 

[Davy Crockett]

Somewhere along the line there must be a golden rule about this. An engineer who built equipment for both federal and civilian sales told me always ground the negative.

 

[wslayer]

AI has different applications. Mostly the reason for putting on the negative is to omit spark when turning on and off. I had mine on the positive side on my 5th.wheel and had no issues, it did what it was intended for.