2012 challenger battery not staying charged

[lwhiteside03]

I was out this year, probably ran an hour trying to charge the battery. once I got to where I was going, the battery light came on. turned the battery off, then when I went to leave, I started one engine, let it run for a few minutes, then tried to start the second engine. then they both died. had to get towed in. Bought a new battery, ran good for a couple of hours, then went out, and the battery light immediately came on. put back on the trailer and went home. open to any suggestions, thanks.

 

[alainm]

That sounds like a bad magneto or voltage regulator and not a bad battery.

 

[lwhiteside03]

yeah thats what i have researched. i am going to purchase the regulator first as i think it is an easier fix that the magneto. Would you go ahead and buy both and change both or somehow try one at a time. (i have 2 engines)

 

[alainm]

I am not familiar with the two engine setup, I am not certain if you have two regulators with one off of one engine supplying the whole boat and the other one is just sitting there doing nothing.
Try testing the voltage at the regulator on each engine, first test the black and red wires coming out of the regulator for the proper DC voltage you should not have more that 14.8V DC no matter what RPM the engine is and no less that 13V DC at idle.

Do you have the shop manual, in it you should have the wiring diagram.