www.iFourWinns.com

What gauge of battery cable did you use for the additional connections? What gauge is the stock battery cable?
It's going to go in front of the stock one in the rear compartment on the starboard side, so a long run isn't an issue.
Thanks

Mine was factory, so I can't help you on the gauge, but in regards to placing the additional battery in front of the first one, you may cause an unwanted list to that side from the significant weight added. One of these days I am going to move one batt to the port side to balance mine out.

_________________
2005 Horizon 250

If it's a short run you can go with 2 gauge (sometimes 4 gauge is OE but to me that's too thin even for short runs). When I added my dual battery system about 7 years ago, I used 2 for the short runs and 1/0 for the longer ones, because I put the 2nd batt over on the port side and the run from that batt to the switch was like 9 feet, 12 actually including the ground cable to the engine. The thicker cable is expensive but you don't want voltage drops during starting. I know the OE cables on my old boat were cheap automotive cables, threw them out the first year I had it and then added the dual batt system a few years later. If making up new cables, get normal battery clamp terminals instead of using wing nuts, they are much more secure and allow enough amps to flow with less resistance since the surface area of the clamp on the large post is much greater than the little post for the wing nuts.

_________________
88 Four Winns 200 Horizon
4.3 OMC Cobra-4bbl
2002 Walker Bay 10/2012 Suzuki 2.5
2008 Walker Bay 8

1998 Jeep Grand Cherokee 4.0/Selectrac
2007 Jeep Grand Cherokee 5.7 Hemi/Quadradrive II

I agree with Lou! I would use marine wire also. It's more $$, but will last longer because its tinned.

I would also install a battery combiner. This will keep both batteries charged up, no matter how you have the battery switch set.

The marine style wingnuts and posts are the recommended method and are more the sufficient for handling the load. I would not install the clamp type. Corrosion is bad enough in a boat without them.

I used 1 gauge when I added my 2 6V battery bank. The larger the gauge the less the voltage will drop over distance. That and a larger gauge will handle a bigger draw. But unless you're talking about starting there's not a much else that'd be pulling a lot of amps. I used a piece of string to get a rough estimate of the totalt distance involved. Turned out to be almost 12' total with all the turns and attachment points were included.

Just be SURE to securely attached the terminals and properly seal the ends. If you don't have the right kind of clamp either pick up an inexpensive hammer type (~$50) or find a local battery shop that can attach ends for you. Just make sure to put the shrink wrap on the wire BEFORE attaching the terminals. Also be sure to use USCG approved terminal covers where they cables meet the batteries. It's one of those inspection items many folks fail to consider, and you don't want to give them an excuse to write you a ticket over it.

Oh and DO NOT SOLDER ANYTHING. Proper mechanical fastening and sealing is enough. By soldering a connection you actually make it 'too stiff' for use in a recreational boating vessel. This leads to the solder getting cracked due to wave action and other vibrations, increasing the likelihood of possible sparking. Just use the recommended kinds of clamps and seal the insulation up tight to them.

Remember to go back every so often and make sure your connections are still snug and free of corrosion.

_________________
-Bill Kearney, 2005 348 Vista

That's some good info. I think I've decided to put the second one in the port side compartment for better balance.
I take it that for that longer/new runs 1 gauge will be sufficient, but I can keep the factory cables on the starter to commom and ground to the closest battery?

You can keep the OE cables for the 1st batt as long as they are in good shape and big enough for the total run from the batt, to the switch and then the ground from the batt to the engine. The common from the switch to the starter again has to be sized for its length. Typically as long as the runs are less then 6 feet total 2 gauge is fine. Now if you have your #2 batt way over on the other side, you to have to upsize the gauge because that total run could be as long as 12 feet if you figure the pos cable from the batt to the switch and the ground from the batt to the engine.

I read some time back the US Coast Guard was recommending that people do not use wing nuts because they often get loose. If you don't want to use automotive style clamps, you can use a nyloc nut (regular nut with a locking nylon insert) that will hold the cable more securely than the wingnuts. I have the automotive style clamps but the marine quality version and even sitting on a salt water mooring 6 months I do not have corrosion problems with the clamps. Usually if you have a lot of corrosion either there is a small crack in the batt case letting out hydrogen gas which is corrosive or water is leaking on top of the batt. I have my batts in boxes and there is no corrosion at all.

_________________
88 Four Winns 200 Horizon
4.3 OMC Cobra-4bbl
2002 Walker Bay 10/2012 Suzuki 2.5
2008 Walker Bay 8

1998 Jeep Grand Cherokee 4.0/Selectrac
2007 Jeep Grand Cherokee 5.7 Hemi/Quadradrive II

From Lou "I read some time back the US Coast Guard was recommending that people do not use wing nuts because they often get loose. If you don't want to use automotive style clamps, you can use a nyloc nut (regular nut with a locking nylon insert) that will hold the cable more securely than the wingnuts."

Thats the way I feel. I just want to say, you can get them in stainless.
Here is a great site (prices) for stainless!! http://www.allensfasteners.com/

here's what Yamaha and Mercury have to say about wing nuts.....

http://www.yamaha-motor.com/outboard/ev ... _no_7.aspx

http://www.perfprotech.com/store/articl ... ments.aspx

http://www.mercurymarine.com/media/merc ... Verado.pdf

_________________
88 Four Winns 200 Horizon
4.3 OMC Cobra-4bbl
2002 Walker Bay 10/2012 Suzuki 2.5
2008 Walker Bay 8

1998 Jeep Grand Cherokee 4.0/Selectrac
2007 Jeep Grand Cherokee 5.7 Hemi/Quadradrive II

Like anything else you'll want to be checking the connections as part of your regular maintenance schedule. One advantage to wing nuts is you avoid putting too much torque on them. Yes, you want them to be tight, but at the same time you don't want to put a wrench on there and risk twisting the post (which I've seen people do) or burn the hell out of your fingers by shorting against two terminals (which makes for a REALLY hideous burn).

_________________
-Bill Kearney, 2005 348 Vista

Thats what is good about the "locking nylon insert". You just need to make them a little bit more than hand tight, they will not back off. Up here in Boston, we also call them "aircraft" or "slip" nuts. I use them all over the boat, radar arch, connections, mount the AIS receiver, windlass and more..

The Merc advisory posted specifically says to solder all connections, as I always do for improved electrical contact. I only spent 4 years of my life in a sub-marine environment, and have a few years of doing thermography since, but who am I to say.

As far as Nyloc... I agree and use them throughout my boat, lawn mower, etc... but I do NOT use them on electrical (battery) connections as if they get scorching hot, and melt, you could damage the post trying to remove. However, I see arguments either way on that one. Since my batteries are only installed 6 mos out of the year, I use No-Ox and check my connections frequently.

_________________
Walt B
"Debt-Charged"
Black '07 H210SS
6.2L Bravo One turning a 21P HIFive
Wakeboard Tower with Perfect Pass Stargazer version
Missouri River; Kansas City, Mo.

It's one thing to handle things in a controlled, precise setup. I'd imagine the requirements on a military sub to be a bit more rigorous than recreational vessels. I was likewise surprised to see that suggestion on the vendor page. When you know it's going to be a rigid setup there's definitely something to be said for a soldered joint. Given how I've seen most boat battery setups I wouldn't think of it as rigid enough.

_________________
-Bill Kearney, 2005 348 Vista

Walt, you are right! Nervier thought of "if they get scorching hot, and melt," But never had a problem in 12 years. As long as there fairly tight, they should not heat up.

Thanks for all the info!