Need diagram to wire-up three (3) batteries.

[anglicomarine]

I bought a 21 ft ski boat w/ 3 batteries. but they don't charge-up properly. I had the batteries tested and they are all good. So next I'm suspecting it is the way they are wired-up. I need a wiring diagram showing required accessories (perko switch), etc. Please help!

 

[arks]

Re: Need diagram to wire-up three (3) batteries.

This setup applies to twin-engine boats but maybe you can figure out how to make it work for you.
http://bluesea.com/viewresource/684