battery charging two or one

nas 632

Cadet
Joined
Apr 29, 2003
Messages
10
I have a 1982 e/s johnson 50hp i have two batteries is it better to have the engine charging one or two batteries i have the usual electrical gear on the boat, at the moment there is only one battery getting charged and the other is spare but i have now fitted some extra lights and a stereo.<br /><br />any help please.
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: battery charging two or one

The generator or alternator puts out whatever it is rated for and does not know if it is connected to one battery or two. I would want one fully charged so that I was sure that I could start my motor rather than two 1/2 charged. I charge one on the way out and the other on the way back.
 

Boatist

Rear Admiral
Joined
Apr 22, 2002
Messages
4,552
Re: battery charging two or one

Nas<br />I charge both my batteries thru a battery isolator and have been doing so for 23 years and never had a dead battery on the water or a battery that did not last 6 years.<br /><br />Only question I have is what type charging system do you have. If you are charging a run down deep cycle wether used for trolling or a house battery and you only have a 4 or 6 amp alternator then probably not a good idea. There are ways to insure starting battery get charged first. Some charging system could be dammaged charging a dead deap cycle for hours.<br /><br />I have found my starting battery after a normal start usually fully charged again in 1 to 3 minutes but I have a I/O with a 30 amp alternator. Have all the normal gear, Vhf radio, Loran C, GPS, Fish finder, Radio, Lights and guages, under deck lights, dual horns, accessory outlets ect.
 

nas 632

Cadet
Joined
Apr 29, 2003
Messages
10
Re: battery charging two or one

Many thanls for the info boys very helpful.<br /><br />Cheers...
 
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