Dual Battery Switches, proper use?

[Fidnee343]

Hello all,

My first post. Great forum. I just purchased a 2001 Cobia 270 with Twin Yamaha 200s ox66 Saltwater series. I'm new to the twins. I have 2 batteries in 2 separate compartments, each with its own switch. I cant remember off the top of my head which brand switch. Whats the proper procedure in using these? I did notice the when only one switch was turned on(to "both" I think), only 2 gauges were on, when I turned other switch, the remaining went on. Im reading conflicting answers or opinions on whether to keep them both turned to "both" when going out, then switching one to off? Or just leave them on "both" period. Pros/Cons? Thanks

[ausnoelm]

absolutely no idea without some sort of wiring diagram or a lot more info.

[DennisG01]

Different manufacturers and especially PO's sometimes do things differently so as mentioned above it's harder for us to guess than it is you since you have them right there in front of you and can trace the wires. But, assuming for a minute that it's what I would expect, then...

Each bank of batteries feeds one engine. The switch determines which individual battery is giving it's juice, or both. The batteries will charge better/faster if all of the engine's charge goes to one battery at a time. The reason for the switch is that you have a standby battery - in case one dies. If you operate on "both" all the time, you could end up killing both batteries at once. I try to run odd days on #1, even days on #2. Although sometimes on a long run, I'll switch batteries or go to both. You can only do this while the engine is running if you have a 'make before break' type switch. You'll have to check the specs for the models you have.

[rodbolt17]

whuwhuwhiuwhu
\
man that last explanation left me all woooooooo.
made NO sense.

the OX66 motors have the capeability to charge a battery that is not selected to run on.
its called a battery isolator.
how yours is wired NOW? no one knows.
how it was wired when neww is very suspect.
riggers cant wire.

[Fidnee343]

Thanks Guys. Ill look at wiring. I guess I was looking for what would be considered "normal" as far as twin motors and 2 batteries and 2 switches. I realize everything can be speculation. They guy I got it from had it for 8 years and said he always turned both switches to "both" and went. Never had an issue. I was just concerned with what Dennis said, as far as both "dying".

[DennisG01]

man that last explanation left me all woooooooo.

I usually only have that effect on women.

But, was only referring to the operation of a switch. Once the charge leads from the engine terminate at the switch, it's the switch that determines the rest, right?

[DennisG01]

Thanks Guys. Ill look at wiring. I guess I was looking for what would be considered "normal" as far as twin motors and 2 batteries and 2 switches. I realize everything can be speculation. They guy I got it from had it for 8 years and said he always turned both switches to "both" and went. Never had an issue. I was just concerned with what Dennis said, as far as both "dying".

It's a safety factor - IF an issue arises, it would only affect one battery.

There's less concern (in regards to the switch position) when the engine is running, although if for some reason the charge output is all of a sudden too high...

"Standard" practice is usually centered around what you're doing when the engine is off. You don't want to chance pulling BOTH batteries down using the stereo, fishfinder, etc.