Second Battery in Islandia

[mortified]

I’ve been working on some renovations to my 2005 Islandia (seats, graphics, Hydroturf, new bimini, etc). The next project I want to tackle is putting a second battery in so we can safely listen to the sound system without it killing the battery.

I read Doc’s post for some info here: Second battery in a Merc powered Islandia

I ordered the same switch that he references in the thread. Is the only real wiring I need to do is to run the new battery positive to the switch and then ground the battery? This just sounds so simple, I'm wondering why I didn't do this before.

Also, my main battery is probably due to be replaced. What batteries would you suggest for primary and secondary?

 

[MightyViking]

I am following this thread as I want to put a second batt in my ’03 Islandia. To ground the second batt do you connect the negative terminal of batt 1 to that of batt 2? Also wondering why didn’t do this sooner.

 

[05sportsterle]

Here is the wiring diagram that came with my switch. i have a radii and fish finder that i run off my secondary battery that works great. no fears of be stranded on the lake with a dead starting battery