"Ken Blevins" wrote in message
...
Three times in two years my cranking battery has failed me.I fully charge
it
,have it checked at a "battery terminal" and three outings later the
thing
will barely turn it over , much less start it.I know the thing to do is to
charge it every time I charge my trolling batteries , but I always figured
that was what the alternator was for.Do you all charge your cranking
battery every time you hook up to charge your trolling batteries.?
Would
you guess a bad battery or faulty alternator?? Or just someone lazy on the
maintaince end???
Thanks
Ken

Well Ken,

You have to remember that typically, all boat manufacturers wire their boats
so that EVERYTHING runs off the starting battery with the exception of the
trolling motor.

So, that means that your livewell pumps, bilge pumps, radio, locators,
accessories, etc., run off the starting battery. Then, if you're like most
anglers, you run the boat for 5-10 minutes, and start fishing. So, each
time you move, you're discharging the battery as you start the motor. IF
you keep any fish in the livewell, you're running the livewell pumps, which
is discharging the battery even more. If you have a radio in the boat, and
play that, or a gps, or any other 12 volt accessories, you're running the
battery down even further.

You then come home and dutifully hook up the battery charger to the trolling
motor battery, topping that off. But I'll bet you never charge up the
starting battery. Unless you're running long distances, your alternator
(assuming it's operating properly) never has a chance to re-charge the
battery.

Have the battery checked for dead cells and make certain it's fully charged.
Then, if the battery is all right, check how your boat is wired. I'd be
willing to bet that everything is hooked to the starting battery.
Disconnect everything but the leads for starting the outboard and connect
all these accessories to the deep cycle battery.

This way, all the things that will run down your starting battery are
running off the deep cycle and that battery is getting charged after each
trip. Also, if these accessories do drain the battery (batteries), the
worst that will happen is that your trip is cut short. But at least you'll
be able to get back to the landing.

I did this with my prior boat, the ProCraft, and that worked great! On the
Cobra, I have the starting battery connected to the on-board charger so that
all batteries in the boat are fully charged after every trip.

Good luck and let me know how things turn out.
--
Steve @ OutdoorFrontiers
http://www.outdoorfrontiers.com
G & S Guide Service and Custom Rods
http://www.herefishyfishy.com