Battery Strategies: Optimal use and maintenance?

Benz Mondi

Petty Officer 2nd Class
Joined
Aug 30, 2010
Messages
125
OK, though I've had my boat (my first one) for almost three years, it stayed in my garage for the last two years until recently. It seems that some of my hard starting and power loss issues are directly related to poor contacts and not enough battery power even though my volt gauge always reads above 12 volts when I start to crank the motor. I've done the forum searching but still can't seem to find the answers that best suits my needs...

I have a three battery set up of all group 24?s with ratings of 550 Cold Cranking, 85 amp hours, and 140 reserve. One battery is brand new (haven?t even hooked it up yet) and two are two years old. I use one for the outboard and two for the trolling motor (motor guide 12/24 volt model). Though I have not load tested the two older ones, let?s assume that they pass a subsequent load test (if they don?t I?ll go ahead and replace them).

Question #1: Do I attach the boat leads to the battery with automotive style battery clamps for a dependable connection?

Thus far I?ve always attached the boat leads which have metal rings at the ends to the battery via the threaded post and just snugly tightened a nut down on top of it with a wrench. Sometimes if I?m rushed, especially when I?m just quickly testing something, I?ll just hand-tight them down. Apparently the last time I didn?t tighten the red end enough because when I went to disconnect the red lead and began to grip the nut, it was burning hot (must have been arching).

Question #2: Since my charging system does at times of prolonged cruising show 16 volts on my volt gauge (I haven?t made up my mind on the whole rectifier solution pro?s and con?s yet ), what would be the optimal schedule for using each battery as the Outboard battery?

Question #3: After a day of using all three, what would be the optimal charging strategy?

Question #4: For periods where the boat isn?t used for a month or more, without using a battery minder or tender, what is the optimal charging maintenance strategy?

Question #5: Assuming I follow the answers for optimal use and charging above, how long could I reasonably expect these batteries to last?

Thanx.
 

Noltz

Petty Officer 3rd Class
Joined
Sep 13, 2012
Messages
87
Re: Battery Strategies: Optimal use and maintenance?

Poor contacts will ruin anyones day. Boat, truck or car it needs good contacts and good cables. I've seen plenty of Fords come in with new starters hooked up right and 12.6V at the battery but just click! when turned over. Corrosion inside the power cables. Put your volt meter on the starter solenoid & engine block, not the battery, and crank. That'll show you how much voltage is getting to the starter itself.

To address your questions I'll try and stay brief. Knowledge comes from 15 years under automotive, not boats.

1) Keep the stud type connections. They're marine standard and have been for a long time. They work, and it's easy to remove when storing the boat. You can use terminal grease with a toothbrush to 'paint' them and keep them clean.

2) I would not recommend swapping batteries around. New one goes on the outboard, two older ones to the troller. Are you hooked up as one battery for 12v, both for 24v? Or parallel & series? And are you hoping to charge your trolling batteries off the outboard during the cruise home?

3) Your outboard battery should require no maintenance. 16V is high, but normal according to other threads. That battery should be happily charged up after a good run, just disconnect it when you're not using it.
The trolling batteries are a good question. I'd be happy to give you examples from OEM setups on diesels or selectable setups used in offroad Jeeps. Jeepers often use marine switches to connect batteries because the'll find themselves underwater from time to time :) Tell me how your trolling motor is wired up.

4) Disconnect all batteries. The outboard battery should be absolutely fine. The trolling batteries must be stored fully charged for maximum life. How to do this easiest depends on how they're wired. Simplest solution is to disconnect both, use jumper cables to put them in parallel, and use the battery charger on a medium setting (10A to 20A) until fully charged. Full lead acid charge is 12.6-12.8V at room temperature after resting 30 minutes. Disconnect your charger and wait 30 minutes before checking, or you may see a "surface charge".
There's more complex ways to do this, and if you want to charge off your outboard during the cruise home we can figure out how to make that work for you. Marine switches are available that let you run from 1/2/Both batteries and you can daisy these to control more. (Scroll down to see marine setups like yours)

5) No idea. Jeep batteries for me last 2-3 years of moderate use. The vibration and pounding takes their toll. I'm guessing if you're out in deep sea swells and they're getting thumped, about the same.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,075
Re: Battery Strategies: Optimal use and maintenance?

My current batteries,1 is an 2008 the other is 2007.
One 650 the other is 550cca.
In my area"HOT" most of the year.The batteries can last 3 years if your lucky like me they can last 6 or more.
My wifes car battery goes after 2 years(again HOT)
Get a load tester.$25 at Harbor Freight.
 

Benz Mondi

Petty Officer 2nd Class
Joined
Aug 30, 2010
Messages
125
Re: Battery Strategies: Optimal use and maintenance?

OK so no need to swap he batteries around. I actually only have two batteries available for trolling in case of emergency. Though the trolling motor can be on 24 volt mode, I've never actually used it that way. It has plenty of power on one battery for my size boat so the other battery is for just in case I need it for the troller or the outboard. I'll test with a hydrometer all three and for the two trollers, keep them charged up once every couple of weeks and verify with a load tester. If I get more than three years out of them then I'm going good. Thanks.
 

batman99

Petty Officer 1st Class
Joined
Sep 13, 2012
Messages
393
Re: Battery Strategies: Optimal use and maintenance?

For my Force 120?..
- Replaced its thin factory #4 Gauge battery wires with much thicker #2 battery wires.
- On battery, use battery "terminal post" instead of factory bolt with butterfly nut.
- Obtained 2.5 Amp Solar Panel from local WallMart/K-Mart store. When boat is stored or being towed, I ensure its Solar Panel "trickle charger" is connected (and facing the sun rays).
- Clean inside of starter and ensure its wires & brushes look great.
- removal all battery cable contacts, apply dielectric grease, then re-install. Thus, getting better connection across different metals.
- Use larger #27 (instead of factory #24) Marine / RV Grade battery. re: EverStart Marine Battery 27DC-850N

For winter storage months, I remove battery and store (on wood boards) inside my basement storage room.

If wondering, I get the impression the Force 120 stator & regulator doesn't produce battery "charge power" under 1,600 RPMs. Thus, when on land I use 2.5 Amp solar panel as a trickle charger. For this, I simply hard wire to battery posts and when solar panel is needed, I simply connect its wire cord joiner. Then, hang off rear or side of boat. Or, lay on the flat floor when towing.

After applying above, all works great. Never had battery problems again.
 
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