Jetski battery 101
Without a doubt, the battery on your ski can cause the biggest amount of grief during your time as a jet ski owner. Every year we answer the same questions from owners who are not familiar with the basic science of batteries.
So lets cover a few important things in just 8 bullet points;
#1 Your battery takes the hardest hit over winter. If you don't use your ski for more than 3 months it can cause serious damage to the healthiest of batteries and may require replacement.
#2 If you look after your battery seriously well, you should get 3 - 5 years of good service.
#3 If you are not using your ski once a fortnight, you will need to invest in a battery charger. We use the CTEK system at $109 - it can be left on the battery full time and has a permanent connection so you don't have to fiddle with your battery terminals when you want to plug it in.
#4 Basic rule of thumb; charge the battery for the weekend once a month to bring it right up to full charge (or if you have an auto charger as above, you can just leave it on). Some ski's will drain the battery faster and require charging every 2 weeks - this can also apply to some dual battery set ups.
#5 A dying battery can take on a charge and seem okay, then be flat the next day. We generally refer to this as the capacity. Once it has suffered damage in a discharged (flat) state or starts to get old, it will be enough to effect this capacity/ability to hold its charge.
#6 Battery brands; new ski's have a genuine Yuasa battery which are the best lead acid battery. When it comes to replacement, the best way to go is a maintenance free Motobatt which are constantly improving their technology and ability to stay healthy if not in use or on charge.
#7 If your ski starts on a cold engine at the beginning of the day (and it hasn't just come of the charger), then you should have no problems with it for the rest of the day. If is sounds sluggish, have it checked before you go out.
#8 Never, ever, jump start your ski with the car running.