Where is the Battery on a WaveRunner, Sea-Doo, or Jet Ski?

One of the simplest yet most perplexing parts of routine battery maintenance is locating the battery in the first place. Because our watercrafts are subject to so many different harsh elements, it is essential that the batteries are kept in top condition. Here, we’ll give a few examples of the most pertinent maintenance procedures and where to find the batteries on the Yamaha, Sea-Doo, and Kawasaki watercrafts.

The battery of the Yamaha WaveRunner is located toward the stern of the watercraft, underneath the passenger seat. The batteries of most Sea-Doos and Kawasaki Jet Skis are located underneath the cover on the bow of the watercraft or in a compartment on rear deck. Newer Sea Doo batteries are under the seat on left side of engine.

The batteries of these watercrafts are very well-hidden – usually due to space limitations and weight balance issues. Keeping your watercraft in tip-top shape means paying regular attention to your batteries by charging, inspecting, properly storing, and cleaning them. I use a Battery Tender Junior and Battery Tender 800 available from Amazon. Neglecting to do so can reduce the longevity of your battery and rack up costs of replacement, so here are some of the most important tasks in battery maintenance.

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The Importance of Battery Maintenance (And Where to Find the Battery)

Regular maintenance and inspection of the battery of your watercraft are essential to its proper functioning and safety of your watersports experience. A full maintenance routine of your watercraft’s battery includes not only charging it, but knowing how and when to inspect it, and when to completely replace it. 

Improper (or a general lack of) maintenance of your battery can result in much more than a simple inconvenience. Neglect of this particular component can result in some pretty dangerous situations, as you may run out of power when you most need it. Apart from this, proper battery care can also extend the life of your battery, ultimately reducing costs in the long-run from having to more frequently replace it.

The primary things to keep in mind when performing routine maintenance (our winterization post) of your battery is to

• Keep it fully charged. Use a smart charger like the Battery Tender Junior from Amazon.
• Store your battery in a clean, dry place (meaning inspect your watercraft after trips! Ensure that there is no water – there shouldn’t be – in the area where your battery is stored. If there is, remove the battery and dry it off if it came into contact with the water.)
• Inspect the battery for corrosion (clean it off if necessary). 
• Ensure that the cables, terminals, and posts are clean. 
• Avoid overcharging the battery. According to Batteries Plus, overcharging your battery can do some serious damage as it causes the acid inside to boil. This can cause your battery to crack or even explode, rendering it completely unusable for your watercraft. Use a smart charger that prevents this.

One of the smaller troubles of battery maintenance is not knowing where to find the battery in the first place! So here, we’ll give a few examples of routine battery maintenance and where to find the batteries on the Yamaha Wave Runner, Sea-Doo, and Kawasaki Jet Ski.

Charging the Battery of Your Watercraft

Charging the battery (read our full battery guide) of your Yamaha WaveRunner, for example, is a bit more complicated than just hooking it up to a few cables and calling it a day. In order to properly charge your watercraft’s battery, you’ll have to remove the unit entirely. While you do so, it would be wise to check the battery for any damage that may have been caused during use and ensuring that the electrolytes are still at optimum levels. 

Once these things are checked, you can then begin to charge your battery by following these steps (example specifically for the Yamaha Wave Runner):

1. Using a 5/16″ socket and sock wrench, remove the nut from the negative battery post. 
2. Remove the cable from this negative post. 
3. With a 3/8″ socket, remove the nut from the positive battery post. 
4. Remove the cable from this positive post.
5. Unscrew the fitting located at the end of the battery’s breather hose.
6. Remove the breather hose.
7. Unhook the male ends of the battery bands from the female ends. 
8. Remove the battery from the Wave Runner for charging.

You’ll find the battery behind the first seat of the Wave Runner (where the second passenger is intended to sit): lift up the cover of this section behind the seat to find the cooler. Lift up the cooler and you’ll see the battery in the storage area on the bottom of the watercraft. 

Replacing the Watercraft Battery

We’ll use another example to discuss the need for regular replacement of the watercraft battery. Maintenance of a Sea-Doo is essentially the Sea-Doo is very similar to that of the Yamaha Wave Runner. It is recommended that the battery of your Sea-Doo is replaced every 4-5 years. To locate the battery of your Sea-Doo, lift up the cover on the bow of your PWC. Note some Sea-Doo batteries are in a compartment on the rear deck of the ski.

Remove the divider assembly, and behind it, you’ll see the battery. Once located, remove the diagnostic connector from the holder and disconnect the positive and negative battery cables. Remove the battery holder screws and disconnect the battery vent hose. Lift the battery from its compartment, being very careful when separating electrical component support from the battery holder. 

When completely out of the Sea-Doo, you will want to disassemble the unit by unlatching the upper tabs of the casing and removing both halves of it. Remove the old battery and insert the new one by aligning the lower tabs, installing the battery post inserts, using electrical grease to do so. 

Once the new battery has been secured in the holder, you need to be sure to check the voltage of the battery and determine whether it needs to be charged before installation. It should read a minimum of 12.5 volts. Install the new battery and you’re ready to get on the water!

Removing Corrosion from Your PWC Battery

Obviously, the best way to treat corrosion is to prevent it in the first place. One of the best ways to prevent corrosion of your battery is to remove it from your PWC if you do not intend to use it for an extended period. Apply a thin coat of battery terminal grease to the terminals, and then place it on a trickle charger. Doing this will prevent a slow discharge of the battery, thereby preventing leakage when the battery gets low or dies completely (dead batteries are more likely to leak).

If you’re going to be leaving your Kawasaki Jet Ski, for example, unused over winter, you’ll want to place the battery in a dry area with moderate temperatures. The battery of the Kawasaki is located in the same place as that of the Sea-Doo: underneath the cover and bin located on the bow of your PWC. 

Lift this cover and remove the bin to access the storage area to find two hatches. The pentagonal hatch on the bottom of the storage area. Remove the five plugs by placing pressure on the center of the plug (you can use a small screwdriver or another small tool to do this) and pull up the hatch. The plugs will easily fall out of the hatch, so be careful not to lose them. 

If you find any corrosion on your battery, one of the best ways to remove it is by applying a mixture of baking soda and water (don’t overdo it!). Give it a few minutes to work its magic and take a small toothbrush or coarse paintbrush to remove the corrosion. Carefully wipe or rinse off the mixture and apply some corrosion spray to protect the battery for the future.

Finding the Battery of Your Watercraft

If you’re planning to perform maintenance on your watercraft but find yourself having trouble locating the battery, two of the best places to look would be toward the stern, underneath the passenger seat, or toward the bow, underneath what is essentially the “hood” of your PWC. If you still cannot find the battery, don’t fret! Your best resource is your user manual. 

Using the resources provided to you with your watercraft will ensure that you provide the best care possible and enjoy a long life with your Yamaha Wave Runner, Sea-Doo, or Kawasaki Jet Ski. You can read more at 5 Reasons Your Jet Ski Battery is Dying.

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