View Full Version : adding second battery

12-18-2010, 08:48 PM
Bought a 2003 MC with tower lights, speakers, inboat speakers and sub. Right now, it is on a single battery. In my former 1989 Prostar, I had dual batteries, one for the sound, one for the starter. Seller told me he had never had any issues with just the one battery. What do you all think? This would have never worked on my old Prostar, only because I guess alternator just wasn't designed for this.

Would say a new x-1 come with all that sound equipment come with 2 batteries?

12-19-2010, 12:36 AM
depends on how you plan to be anchored at the sandbar, partying.....stereo cranked, beer in hand, music cranked....if you're like me, the second battery is a must. having a larger / newer alternator doesnt help when the engine is off and the stereo is cranked.....add the battery and intall a battery combiner. there are plenty of good threads here with install ideas. i used a blue seas 7610 acr...been happy with it

12-19-2010, 10:42 AM
I think you answered your own question. You upgraded your battery capacity in the old boat and presumably the new one pulls more amps.
I'm with robin on the Blue Sea ACR to link them. I did this on my X2 prior to last season and it worked great. Like your prev install I ran one batt just for the stereo amps and the start batt for the remainder of the functions. Works great. No worrying about switching batteries for charging purposes, the ACR keeps the loads completely separated all the time, yet they charge simultaneously off the alternator or battery charger (ie: hook your charger to either battery and the ACR links them automatically to charde both).

12-19-2010, 11:26 AM
Look up diesels thread on duel battery's. Thats how I hooked up mine and have had no problems

12-19-2010, 11:52 AM
Every boat I have ever owned had two or three batteries in it with disconnects. I will be installing a second battery in my 93 after the holidays. That is one of my winter projects. I actually run with all batteries on line and just leave one battery on line when parked while listening to music or using lights. If my boat is sitting or stored then all batteries are switched out or even removed completely. Probably overkill but as much time as I spend on the water---I have only been towed twice in any of my boats. Embarrassing. Sometimes there was no help in sight and calling for help would be hours away.

12-19-2010, 03:33 PM
I did the same ACR installation as Thrall. Works great. It's always nice to have the extra battery especially if you boat on larger lakes.

12-19-2010, 06:02 PM
thanks to all

12-19-2010, 09:32 PM
I've got a 2008 X-1. Pretty loaded stereo wise. 2 huge amps. Single battery.

I was told the accessories (i.e. stereo) would shut off before I lost enough battery power to start the boat. Is this true? Even if it is, I don't want to rely on this. So I am going to add a battery.

Question: Is there a way, with 2 batteries, to run 1,2 or even 3, ballast pumps without the engine running, and not have too much amperage drop? I was told to run 2 pumps max, and only while the engine was idling at 1000 rpm, to avoid burning out pumps.