boat batteries

so i put this in boats/motor section, but may not get many looks…

OK so what is the proper way to run with my batteries? I have one that is a cranking battery, and one is the multipurpose. it has the electronics hooked to it. I have a battery selector switch and usually crank up on either battery, run with it on that battery for a while and then switch over and do same thing with other. I heard not to run with selector on “Both” in case your electronics kill them due to a problem in the electronics. I don’t really agree, but whatever.

I have only had my other two batteries for two years so am I not running them right? i have 225 hours on motor over that time so it’s not like i’m letting it sit up.

B.O.A.T. Bust Out Another Thousand!

2016 Sea Pro 219

Use a dedicated battery for cranking and the other for electronics, after cranking and running a bit switch over to your other battery to keep it charged.

I learned the hard way running Both batteries… Most outboard charging systems can’t handle the stain of trying to charge two batteries at the same time if they are down a bit. I had my trolling motor batteries tied into the perko switch and figured it wouldn’t be an issue charging them while running. Burnt’ up my regulator. I wouldn’t have a boat without a voltmeter to watch battery condition, and now most depth finders have one built in with an adjustable low voltage alarm… depending how long and how much load you have on your system while parked… stereo etc. A fully charged cranking battery is a stress saver.

Thanks Fred,
that makes sense and is what I’ve always done pretty much. I was just curious as to why they both only lasted 2 years…
O’well

B.O.A.T. Bust Out Another Thousand!

I find that my batteries didn’t last as long when they were kept on a charger all the time.Now I’ll charge mine when I get home and then the night before going out.Sounds like you’re doing nothing wrong.Maybe you can catch up with Ralph at the landing or I’m sure the guys at the eye strike store can tell you how to find him.Buy some batteries from him and I bet he’ll give you some words of wisdom.

I have a blue sea charging relay. It isolates the start battery from the house battery as long as the start battery is below 12.25 volts. When the start battery reaches full charge the relay will close and start charging the house battery. When the engine is off the relay opens so you can’t accidently kill both batteries. However, if the start side does die you can switch to the “all” position that gangs both sets together to get you started.
https://www.amazon.com/s/?ie=UTF8&keywords=blue+sea+charging+relay&tag=mh0b-20&index=aps&hvadid=78683853375596&hvqmt=e&hvbmt=be&hvdev=c&ref=pd_sl_6xudf1sjm3_e

ZX