How to Charge a Boat & WaveRunner Battery

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Charging the battery on the Yamaha Wave Runner doesn't just mean hooking up some jumper cables. It means removing the battery from the Wave Runner, checking it for damage it may have sustained in the course of use, and ensuring its electrolytes are at optimum levels. Only after completing these maintenance checks do you connect the battery to the charger.

Items you will need

  • Socket wrench set

  • Silicone-controlled rectifier-type battery charger

  • Safety glasses

  • Rubber gloves

Remove the nut from the negative battery post, using a 5/16-inch socket and socket wrench. Remove the cable from the negative post. Change to a 3/8-inch socket and remove the nut from the positive battery post. Remove the cable from the positive post.

Unscrew the fitting at the end of the battery breather hose and remove the breather hose.

Unhook the male ends of the battery bands from the female end of the battery bands. Lift the battery out of the Wave Runner and move it to the charger.

Inspect the battery compartment of the Wave Runner for liquid that could indicate the battery case is cracked. If there is no evidence of acid in the battery compartment, inspect the battery itself to ensure the case and terminals are neither damaged nor corroded. Check the electrolyte level in the battery, refilling it with distilled water -- not tap water, not spring water, but distilled water only.

Look at the charger to ensure it is not plugged in. Connect the positive lead from the charger to the battery first, then connect the negative lead from the charger to the battery. Set the voltage you want to to charge to (14.4 volts for a wet cell battery; 14.2 volts for gel cell batteries) and plug the charger in. If you use a silicone-controlled rectifier-type charger, it shuts off when full charging is complete.


  • When working with or around batteries, wear safety glasses at a minimum. Rubber gloves also may be required.


  • While the Yamaha owner's manual says specifically that you should follow the recommendations for the battery charger you use, it also says, "Don't charge a battery hastily."
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