Battery keeps dying

[tigermuskie]

I have a newer four stroke merc 40hp. How does it charge/maintain the battery? Magneto? I put new battery on runs for 3/4 day, motor warning beep goes off. loses power and dies eventually. Does not run without battery which sucks! Learned the hard way and paddled home.

Funny part is the pull cord that came with. What use if motor does not run on own power?

Any tips would be appreciated. thanks

JB