Battery Question - Maxum Boat Owners Club

racer2c · 07-06-2006, 05:28 PM

When I took possession of my new boat I asked the guy who was "rigging" it out how often I should throw the battery on a charger. He said during the season you don't need to at all. He said I could go a step further and do what he did on his 21 foot runabout and add two deep cycle marine batteries, one for accessories so you can jam the stereo all day while at anchor and one for engine ignition. He said even if I don't go with two, I should switch out to a deep cycle.

Thoughts, suggestions?

Thanks!

3388sam · 07-06-2006, 09:38 PM

- here's a post from awhile ago.

Quote:

Couldn't agree more about radio be an important piece of emergency equipment!

One reason I have hand held as well a permanent radio- small boat, one battery- it dies or goes under water - no juice, no radio.
Makes a great case to install a second battery with a switch on any size boat.
We have 3 on our 21', 1 starting and 2 house batteries, but we can configure any way with the switches.
Easy and inexpensive to add a second battery!

Finding room is the only problem- Some times you might have to mount the extra battery on the other side of the boat and use long battery cables.

The battery switch is the key- you have a section switch for bat 1, bat 2 and both.

On the back of the switch there are 3 posts. Run 1 each positive cable from each battery to the switch and then 1 cable from the switch to the starter (you just disconnect the red + cable from the current battery and move it to the switch)
You can then either tie the grounds together or just find a new place to attach the ground from the new battery to the block.

With the switch set on both you are running and charging both batteries. If you decide to just turn the engine off and listen to the radio- just switch it to one of the batteries. If you run it down just switch to the other, start up and switch back to both!

racer2c · 07-07-2006, 12:14 AM

Thanks, but on my little 18ft I have 1.off 2. alarm, and 3. ignition.

3388sam · 07-07-2006, 01:31 AM

You need a battery switch - not your ignitions switch. You need to install this to hook up two batteries. It's a manual switch you turn by hand to use batt #1, batt #2, or both at the same time.
Cost about $25.00, and you now will have a back up if one battery goes dead. Pretty cheap insurance so you won't spoil a great weekend on the water!

Maxum2300SC · 07-07-2006, 02:11 AM

what I found to be the most effective and logocal way to wire a dual battery, dual battery charger (if you have one, if not just take it out of the picture). With this way you are guarenteed NEVER to have a dead starting battery, it is totaly isolated, if that .1% chance that it dies, switch over to the house battery. 3 switch model, combiner is the way to go for a peace of mind.

No 1/2/all switches, 3 on/off. the all mode will kill batteries. if one battery is dead and teh other is full and you have the switch set to ALL, guess what, the dead battery will eat the full battery. With the combiner you loose this effect.

http://maxumownersclub.com/gallery2/...faeac015e97c85

Brit Rider · 07-07-2006, 04:10 PM

Do you have any additional kit on board such as audio amplifiers etc?

a single cd headunit will run for many many hours without running a main battery down. plus you can always start the boat up once in a while to charge the battery should you be concered.
I will not be putting my 1800sr3 onto duals though my last boats, a Super Air Nautique, had a hell of a lot of additional kit like stereos and ballast pumps etc... so 2 batteries was a must. we eventually went to 3.

2 battieres, quick 101
the basic idea is that you have 2 independant batterys that are joined via a switch (perko makes a good one very cheaply). the switch allows for 2 battery operation (both mode), this lets the alternator charge both bats and the starter to feed off one. when you want to pull up and just 'jam some tunes' then you need to move the switch to '1', this will allow your stereo to run off the stock number one battery whilst totally isolating the second battery - and starter which should be on bat 2.

if you run battery 1 down then you just move the switch to the '2' setting and start your boat - f done correctly this will be a fully charged isolated battery.

couple things to remember - you MUST wire your boat starter AND ground off one battery ONLY!. The number '1' stock battery can be left to run all the accessories. if this is not done the whole system becomes redundent and could do something similar to what Maxum2300sc picked up on.

if battery 1 is totally dead (unlikely as most headunits shut down at anyhting fromn 9v to 11v) then you can charge it back up back home or just throw the switch to 'both', start the boat (the charge will then be being shared so unless bat 2 is pretty full it may struggle but will work - run the boat for a few hours and you'll be back upto an almost full charge on both batteries. There are things you can do to speed it up, i.e. once bat one has got a bit more charge in you can switch over so the alternator charges this one only.

racer2c · 07-07-2006, 10:59 PM

Thanks for the info guys!

What about switching to a deep cycle battery? Is that recommended?

Brit Rider · 07-08-2006, 05:34 AM

If you install a 500 watt plus stereo or a poop load of lights on board then yes.

if your boat is stock, or close too then it will be a waste of money.

The benefit of deep cycle is that it won't fade like some batteries do over time if you keep running it right down then charging it back up. In your boat it will probs never get too low to start, let alone be totally dead.

IF this really worries you a better investment would be a standard marine grade battery, 4 metres of 2 guage power wire and a perko switch.

Don't sweat it

racer2c · 07-09-2006, 02:55 AM

Quote:

Originally Posted by Brit Rider

If you install a 500 watt plus stereo or a poop load of lights on board then yes.

if your boat is stock, or close too then it will be a waste of money.

The benefit of deep cycle is that it won't fade like some batteries do over time if you keep running it right down then charging it back up. In your boat it will probs never get too low to start, let alone be totally dead.

IF this really worries you a better investment would be a standard marine grade battery, 4 metres of 2 guage power wire and a perko switch.

Don't sweat it

Cool. Six hours on the water today with the stereo cranked for hours and starting and stopping the engine dozens of times. I think I'm good.
it's just that in my last boat (an older 2 stoke outboard bowrider) I was always having battery problems.
We had seven on today, four adults, two teen agers and one 12 year old. We were surprisinly comfortable and weren't tripping all over each other. I like the recessed seats on either side engine and my passengers found those to be the most comfortable. They allow more cockpit space than boats two and three feet longer that have the bench seat.

Franco_2100SC · 07-10-2006, 01:07 PM

Here's my 2 cents...
On smaller Maxum's I think having two identical batteries is the way to go. I disagree with using the both position, however. I prefer the second to be an emergency battery. To keep charged, start on battery 1, go someplace, and prior to return switch to batterty 2 and return. This way you always have 2 hots, and the charging load on your system will be identical. As pointed out the "both" position can result in the bad battery bringing down the good one. I've heard all kinds of nightmare stories about folks damaging electrical circuits when using the both position, and while they are just chatter, the safest course seems to be the one I outlined above.

KKKKFL