Starter battery question

[walleyewizard]

I'm having trouble keeping my starter battery charged up all day long. I'm running 2 locators and the live well and after 4-5 hours my starter is almost too low to start my motor. Would hooking 2 batteries in parallel solve this problem or does anyone have any other ideas? Thanks

[hoggs222]

Are you running everything off of the starter battery? If so, it would be a huge difference if you got a deep cycle battery.

[walleyewizard]

Yes, all electronics are hooked to the starter battery. The trolling motor has it's own batteries. I just don't think 2 locators and a live well running on a timer should drain the battery that quick.

[eurolarva]

Get a DC volt meter and hook it up to the battery. When the motor is not running with a full charge you should read about 12.75 Volts. Start the motor and goose the throttle to about 3000 rpms and the voltage should go up to over 13 volts. Does your motor have a Tach? If so does it work? . You may have lost your voltage rectifer/ regulator. If you ever accidently hooked your battery cables up backwards even for a second the rectifier acts like a real expensive fuse and will blow and then your battery wont charge.

[upnorth]

How old is the battery? They lose their ability to hold a charge after a while. I could be that it is just getting old and tired

[walleyewizard]

This is on a brand new rig, just bought it this spring!!! The dealer claims the battery and motor are o.k. That's what makes it so puzzling. I just don't want to get stuck dead on the water.

[upnorth]

Does it seem to charge up when you run the motor? Or do you have charge it before it will recharge?

It should charge the battery whenever you run the motor and it should hold a better charge than that new, unless you have a small crappy battery or it may be defective.

[Giant_Jackpot]

How big is your gas motor? Or more to the point, how many amps does your alternator put out? You say this is a new rig and that means the battery may not be big enough to handle the load. I say this because the dealer is going to put in the cheapest battery they can. Not knocking the dealer, just stating fact. Two batteries would help but for your situation I think one “big” battery would do the trick. Consider a new 31 series deep cycle for the job. Some folks might tell you not to run a true deep cycle for the starting battery but I have been doing it successfully for years. If you take good care of the battery with proper charging and maintenance, it will last many years.

[walleyewizard]

I'm thinking it's the battery too. It's an Everstart battery that get's fully charged (+13) according to my locator gauges. I had this happen on a previous rig, but it was after running the live well and locator for 8-9 hours, not 3-4 hours.

[BobT]

You're right. Some of us would not recommend using a deep-cycle battery as a starting battery. This is hard on both the battery and the starter because the deep-cycle battery is not designed to supply the level of current demanded by a starter. Since the battery will not efficiently deliver the current demanded, the starter itself may be getting short-changed and excessive heat could result. This will over time degrade the starter and the battery prematurely.

Bob

[Whoaru99]

One question is how big is the battery you are having concerns about?

Maybe it's just a battery that has small capacity. Somewhere on the battery should be the CCA/MCA rating and maybe, if you are lucky, it might show a reserve capacity in minutes or Amp-hours. This information would help determine if there really is a problem, or if it's "just" a case of an undersized battery.

I believe you can get dual purpose batteries that work pretty well for an applications where you have both starting and some continuous loads.

[Giant_Jackpot]

Quote:

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You're right. Some of us would not recommend using a deep-cycle battery as a starting battery. This is hard on both the battery and the starter because the deep-cycle battery is not designed to supply the level of current demanded by a starter. Since the battery will not efficiently deliver the current demanded, the starter itself may be getting short-changed and excessive heat could result. This will over time degrade the starter and the battery prematurely.

Bob

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BobT,

I agree with you to a point but if your starter is grinding long enough to generate excessive heat then I would find out why the motor isn’t starting right away. I have run both regular and deep cycle batteries for my outboard (70hp four stroke Suzuki) and there is no difference in how fast the motor spins when I hit the starter. I knew I would get some disagreement but all I can offer is my experience. I checked the Trojan Battery web site and for the SC225 deep cycle which is the group 31 I am using, and they list it is having 665 cold cranking amps (CCA). Their smallest marine starting battery lists 420 CCA. Exide lists their middle of the road marine starting battery at 525 CCA. My guess is that a lot of dealers put in these smaller starting batteries due to cost and they have LESS power than the deep cycle I am using. Hard to argue with the numbers!