Car battery as a starter battery

[Arkman]

This may be a dumb question...I don't know. I've got a an old car battery that is still mostly good. I was planning on recycling it but I go to thinking, I've got an electric start i don't use because I don't have a battery. Could I use this one?

It was my understanding that you should use a proper battery for this because its really hard on car batteries to be drained and charged over and over again. But is it ok to use (probably just for this weekend) to start my boat motor?

If all I'm going to do is make it so that battery doesn't hold a charge then I don't really care, but I wanted to make sure it wouldn't do any more damage.

 

[v_fourmax]

Re: Car battery as a starter battery

As far as the batteries ability to start your engine the car battery will perform that function just fine.

Biggest draw back would be the car battery is generally not designed to take the stresses, vibrations and the pounding that a battery can be subjected to in a marine environment and could suffer internal damages/failure as far as the plates breaking loose and shorting ect.

Would work though and if you were just going to junk a good battery anyway cannot see the reason not to run it as long as it held up. May never give you any problems or fail earlier than its lifetime as well.

Also after reading your post since apparantly you are using a rope start bypassing the electric starter with a small boat you probably will not be slamming down on waves and such and the chances of the battery prematurely failing would be reduced by that as well.

 

[wifisher]

Re: Car battery as a starter battery

I have to agree with v_four. The battery is junk to you anyway, right? It will not hurt anything to have it hooked up to the motor even if it is dead. Put it in, and use it as long as you can. If it dies, you are out nothing.

 

[Arkman]

Re: Car battery as a starter battery

OK, thats what I figured. I just wanted to make sure there isn't anything I'm missing. As far as waves and such, you're right, I don't head out in major waves. There isn't very much slamming at all.

Thanks guys!

 

[NYBo]

Re: Car battery as a starter battery

As long as there isn't a short inside the battery that could damage your charging system, go right ahead and use the battery.

 

[Arkman]

Re: Car battery as a starter battery

I have no reason to believe there would be a short inside the battery, but if for some reason there was...My motor doesn't charge the battery. The battery is simply there for starting after that the motor doesn't do anything to the battery.

Could this still cause an issue? A short in the battery?

 

[SolingSailor]

Re: Car battery as a starter battery

No, probably not. A starting battery is designed to be recharged immediately though. Not recharging until ahore later will further shorten the battery's life throught sulfation of the plates.

 

[j_martin]

Re: Car battery as a starter battery

I'm there with you on using what's available. Only caveat is that a weak battery is very hard on series wound or permanent magnet motors because at reduced voltage they draw much more current and get much hotter. Marine starters run expensive. If you quit trying at the first indication of the starter slowing down, you won't hurt anything.

 

[sw33ttooth]

Re: Car battery as a starter battery

i would say besides the pounding and abuse of waves other advantage of marine batery is its power abilty to take a draw of a radio, fish finder, lights, ect for hours where as your car battery really isn't but if your only useing it to start wont matter. as for it ruining your charger/coil cant see this happening any more then with a marine battery. fyi, i'd do it with out thinking twice but some people think that may be frownd upon useing car parts in marine apps.

 

[j_martin]

Re: Car battery as a starter battery

Theoretically there's a difference between a marine battery and a car battery. Practically, there really isn't any. A deep cycle battery has a heavier, coarser plate structure so it can withstand fairly deep discharging without shedding material (and capacity) into the bottom of the tank. Eventually that's the failure mode of all wet cell lead acid batteries.

AGM batteries are by far the most rugged, and most expensive. I applications where they won't cause damage with their extreme charge acceptance capability, they are hard to beat.