Battery switch and charging
- Thread starter patrick16
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Hookup1
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First you need to determine how your boat is configured. Get yourself a voltmeter.
With engine off (assuming single engine 2 batteries) measure battery voltage for both batteries. Should be around 12.8 volts for each of them.
With switch in A position start the motor and measure battery voltage. The A battery should be around 13.1 volts. The B battery will either be around 12.8 volts (not being charged) or around 13.1 volts if it is being charged.
With switch in B position start the motor and measure battery voltage. The B battery should be around 13.1 volts. The A battery will either be around 12.8 volts (not being charged) or around 13.1 volts if it is being charged.
With the switch in the both position if you start the motor both batteries should read 1around 3.1 volts. Most GW boaters will tell you not to use the both position for charging - its there for emergency starting power,
If you find that your setup is not charging both batteries while in the A or B position (not both position) you can add a secondary charging shunt or a battery isolator. This will allow your motor to isolate the two batteries and properly charge them. There are numerous posts on this site to help you with that.
With engine off (assuming single engine 2 batteries) measure battery voltage for both batteries. Should be around 12.8 volts for each of them.
With switch in A position start the motor and measure battery voltage. The A battery should be around 13.1 volts. The B battery will either be around 12.8 volts (not being charged) or around 13.1 volts if it is being charged.
With switch in B position start the motor and measure battery voltage. The B battery should be around 13.1 volts. The A battery will either be around 12.8 volts (not being charged) or around 13.1 volts if it is being charged.
With the switch in the both position if you start the motor both batteries should read 1around 3.1 volts. Most GW boaters will tell you not to use the both position for charging - its there for emergency starting power,
If you find that your setup is not charging both batteries while in the A or B position (not both position) you can add a secondary charging shunt or a battery isolator. This will allow your motor to isolate the two batteries and properly charge them. There are numerous posts on this site to help you with that.
I have the same model/year, but with a third battery - so in my case: a start battery for each motor, and one for the house.
Whether or not you're charging both depends on your motor and wiring. The Yamaha's have an auxiliary charge cable that should be connected to the "other" battery. If you have one battery designated for house, most likely that motor's auxiliary charge cable is charging that. It's a much smaller cable (14ga?) coming off of the motor's bundle, and would be connected to the post on your switch that is also connected to that battery - most likely "B".
If you don't have that charge lead, then I don't know how you could be charging both batteries unless the switch was set to "Both".
Whether or not you're charging both depends on your motor and wiring. The Yamaha's have an auxiliary charge cable that should be connected to the "other" battery. If you have one battery designated for house, most likely that motor's auxiliary charge cable is charging that. It's a much smaller cable (14ga?) coming off of the motor's bundle, and would be connected to the post on your switch that is also connected to that battery - most likely "B".
If you don't have that charge lead, then I don't know how you could be charging both batteries unless the switch was set to "Both".
SkunkBoat
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Agree with the above, you will never know your configuration unless you measure and/ or unscrew it to see what’s what.