Dual Battery Questions

[corpusmalibuguy]

I know there are alot of discussions on this topic, but I have looked through alot of them and still have a few unanswered questions. Any help would be appreciated.

I am trying to run dual batteries with a perko switch. The first question is how to run the ground wires from the batteries. I believe that I just run one ground wire from one battery post to the other, and then keep the original ground wire running to the first battery.

I am also a little confused by the diagram that came with the perko switch. It has a wire that runs to the starter. I can't remember exactly but I think I only have one wire coming from my engine to my battery right now. I would assume that that single wire splits off at the engine somewhere and goes to the starter and alternator. I would assume that this wire needs to be run to the Perko switch now but I am not sure.

My last question concerns the power wire that runs from the battery to my accessories. Does this need to be run to my perko switch, or kept on the battery.

Finally, I was going to use 4 gauge wire, but can use thicker wire if necessary. Is this a must or is 4 gauge good enough? Do I need fuses inbetween the battery and the perko switch or not?

I may not have written this very clearly, so I can add info as needed. If anyone has any detailed diagrams that would be awesome. I have an 05 VRide by the way. Thanks in advance.

[RiverRunner]

Existing positive wire goes to the perko switch.

Add a wire to terimal 1 to your starting battery

Add a wire to terimal 2 to your new stereo battery

Add another ground from the first battery to the second

Connect all stereo equipment (amps, etc.) to the second battery

Battery 1 will be your starting battery and battery 2 will be your stereo battery

Start the boat on 1 and then put it on ALL to charge both batteries as you are riding

When you stop put the switch on 2 and run your stereo, back to 1 to start and ALL while riding

[corpusmalibuguy]

Thanks Ken for the help. i guess what I don't understand is how my stereo is going to work if all my accessories(i.e. the acc switches on the dash, and my headunit) are running off of battery #1, or does that stuff attach directly to the perko switch? Also, what about inline fuses? Necessary or not?

Existing positive wire goes to the perko switch.

Add a wire to terimal 1 to your starting battery

Add a wire to terimal 2 to your new stereo battery

Add another ground from the first battery to the second

Connect all stereo equipment (amps, etc.) to the second battery

Battery 1 will be your starting battery and battery 2 will be your stereo battery

Start the boat on 1 and then put it on ALL to charge both batteries as you are riding

When you stop put the switch on 2 and run your stereo, back to 1 to start and ALL while riding

[corpusmalibuguy]

Ok, I finally got around to installing dual batteries with a little help from Ken. I think everything went well. The switch seems to work as advertised. The only strange thing that I am not quite sure how it is happening is that even on battery #1 by itself my amplifiers still work. They are attached to battery #2. I am not quite sure how this is happening, unless the #1 battery runs back through the switch to the connections on my #2 battery. Anyone have any opinions, or is this normal? I would have thought that they would only work in #2 or Both.

Anyway, I also left my Marine Priority Start on my #1 battery. It basically just shuts off the battery if the voltage gets below 12v. I figured I already spent the money on it, and although not likely with my new setup, I guess I could still inadvertently drain my #1 battery to a point that it would not be able to start the engine. Anway, just a little more insurance against a dead battery.

I also ended up using 2 gauge wire from an auto parts store. I originally bought 4 guage, but after seeing that the cables coming off my alternator to the battery were 2 gauge, I just wanted to make sure they were big enough.

Overall not too tough to do. I think it took about an hour and a half once I got all the right parts. Thanks again Ken for the advice.