Battery switch operation

[king5899]

What is the proper way to use a battery switch.(besides the obvous turning part) I was reading in the owner's manual that you should never turn it with the batter running. So let's look at this example:

I hang out and run one battery down. I turn the switch to the other battery to start the engine and it starts. Do I then turn it to the both battery position to charge both of them?

Is it best to start the boat off both batteries even if one is dead, therefore charging the dead one while using the starting power of the good one?

Any input would be great.

Thanks,
MJK

 

[Sandy]

I'd think the manual would say NEVER turn the battery switch OFF while the engine is running to avoid frying the alternator & possibly other circuits. A switch installed in 1998 would most likely be the "make before break " type so it should be safe to switch between batteries if you want to charge a different one underway. Attempting to start the engine with switch on BOTH if you know one battery is very low will only rob starting power from the higher charged one as it shares it's potential & current with both starter and low battery. Just use the good one if it will start, or BOTH if both are low and will not start individually. Underway, switching to the low battery only will charge it fastest. Next trip switch to the other battery, or charge one on the way out & the other on the way back.

 

[PascalG]

battery switches have the both position between 1 and 2 so that you will never disconnect the batteries while the engine is running. The only risk is accidentally going past 1 to OFF and damaging the alternator.

if you know one battery is weak or dischaged, dont' start in the both position.

when switching to recharge one then another keep in mind that is takes a while to recharge and that at low idle your alternator doesn't produce a lot of power. so dont' switch too early...