Adding a second battery to my pontoon boat

[jppontoon]

I boat on an extensive river system and the thoughts of getting stranded does not hold any appeal. Without really knowing what I needed I purchased a blue seas battery selector switch (6007). Seems pretty straight forward to install but my question is will my Honda 40 4stroke with a 12v 10A DC output charge both batteries. Next question is I need to replace my existing battery anyway so what should I put in for a starter and house battery? Any help would be appreciated.

 

[Bamaman1]

Re: Adding a second battery to my pontoon boat

It's easier just to have a good starter jumper box to take with you as a backup. Some even have air compressors to blow up your water toys and/or air mattresses, etc. I also carry jumper cables, as I can always flag down another boater to jump me off.

A second battery would require a special switch, and hooking it up gets complicated.

You really shouldn't worry about this. Have you ever seen a 40 Honda not start?

I like car batteries for use in boats if they're not going to be drained by a trolling motor. They're cheaper and last so much longer. I think my last auto battery lasted me 10 years, and I never even had to charge it in the Spring.

 

[Silvertip]

Re: Adding a second battery to my pontoon boat

Whether or not you actually "need" a second battery depends on the electrical load imposed. Unless you have a high power audio system, trolling motor, or other high current draw items, a dual battery setup is not necessary. But since you seem convinced you need one, you should have a standard Marine Starting Battery for engine starting duty and a Marine Deep cycle for the house (accessory system). For your engine, a group size 24 would be adequate for the engine. Again, depending on the accessory load, a group size 24 or 27 would be more than adequate. Bigger is always better when it comes to buckets of electricity. Since you will have a dual battery switch, use the switch as it was intended. Set it to BAT 1 to charge BAT 1. Set it to BAT 2 to charge BAT 2. Since the engine charging system has limited output, don't use BOTH setting for charging. Do one battery at a time and you will be fine. Remember though, deeply discharging either battery means it will not be recharged on a 10 minute run back to the dock. There are many ways to wire a dual battery system. Figure what you want it to do for you and wire accordingly. There are many diagrams on this forum.

 

[jppontoon]

Re: Adding a second battery to my pontoon boat

Thanks for the help. I really think I like the idea of a second battery in my situation. The boat is moored off shore so now shore power and would like to limit what I need to lug.

 

[Silvertip]

Re: Adding a second battery to my pontoon boat

Thanks for the help. I really think I like the idea of a second battery in my situation. The boat is moored off shore so now shore power and would like to limit what I need to lug.

OK, but be warned that leaving a battery partially discharged is a good way to send it to an early grave. So spending a day on the boat and then making a short run back to the mooring will not have it fully charged. How do you intend to do that without shore power. Yes -- solar panels are available but again, it is all about OUTPUT. The $20 Harbor Freight solar panels are not chargers. They are best described as maintainers to keep a fully charged battery topped off during long periods of down time. A proper sized solar panel is expensive, a target for thieves, and would be half the size of your boat.