Need advice on Battery Charging Issue

[Uplate]

Hello.

My port Engine would not start and I had to use the Crossover switch to get it started. Starboard would fire right up. I looked hard for a Diagram showing what battery powered what on my boat and could not find any specifics, even in my manual.

Pulled out the battery shown as new in the diagram and had it tested, it would only pull 140 Amps out of rated 700. Replaced battery and port starts right up. Not sure what the small wingnut terminal connection does on this battery but the engine room lighting went out when I disconnected it. So thats at least one thing it powers.

Now I am having issues starting my Starboard engine and the VM on the dash reads lower than port, usually by 1-2 volts.

So my question is, can a bad battery cause a low voltage reading on the VM, or is this reading Voltage from the alternator?

I am also confused as to what the parallel wired batteries are for (Assuming Starting Starboard engine for one) and also how the Crossover start switch works with what batteries?

Any help appreciated.

 

[fwebster]

I don't guess at answers here, so I'll let another 310DA owner tell you the wiring diagram.............however, in smaller cruisers, Sea Ray usually hooks 2 batteries in parallel for the house and one side starting; the other side is just for starting and the generator is a stand alone system.

I do know that the ring terminal connecting the bilge lights to one battery is probably some previous owners fix for a problem. When you turn off the battery switches, all that should get voltage are the bilge pumps.

The dash panel volt meter is the voltage across the port or stbd battery bank. With the ignition switch in the on position you should see the battery voltage.......with the engine started and running, you see the voltage across the battery with the alternator functioning......off, it should read 12.6v or a little higher; with the alternator running look for 13.5 to 14.0 volts. If the voltage is 12.0 or lower it indicates a week battery. In that case the actual voltage with the starting load is applied may drop to 8 or 9V and most ECM controlled engines require a minimum of 10VDC to run.

 

[Uplate]

I don't guess at answers here, so I'll let another 310DA owner tell you the wiring diagram.............however, in smaller cruisers, Sea Ray usually hooks 2 batteries in parallel for the house and one side starting; the other side is just for starting and the generator is a stand alone system.

I do know that the ring terminal connecting the bilge lights to one battery is probably some previous owners fix for a problem. When you turn off the battery switches, all that should get voltage are the bilge pumps.

The dash panel volt meter is the voltage across the port or stbd battery bank. With the ignition switch in the on position you should see the battery voltage.......with the engine started and running, you see the voltage across the battery with the alternator functioning......off, it should read 12.6v or a little higher; with the alternator running look for 13.5 to 14.0 volts. If the voltage is 12.0 or lower it indicates a week battery. In that case the actual voltage with the starting load is applied may drop to 8 or 9V and most ECM controlled engines require a minimum of 10VDC to run.

Thank You Frank. This is starting to make sense. I think I will test and/or replace the two batteries that are in parallel hook up.

The Ring terminal, looks really stock to me and not a hack from previous owner. But I could be wrong.

I do appreciate your input. Going to replace those two in parallel.