Can You Jump Start A Jet Ski?

Imagine you are having a great day on the water, and suddenly your jet ski will not start. You are out in the middle of a lake with nowhere to go. You flag down the nearest boater and he has jumper cables. Is jump-starting a jet ski OK to do? There are dangers and risks to jump starting a PWC, so it is important to know the dos and don’ts before you choose to do this. 

Can you jump start a jet ski?

Jump starting a dead battery on a jet ski is OK if you are stuck in the water with a dead battery, but it is not recommended to do on a consistent basis if you have a dying battery. If you jump start your jet ski, you can risk damaging your sensitive electronics with too high of voltage.

Many times, when a jet ski will not start, there could be additional issues or reasons that it will not start besides the battery.  It would be wise to check out your jet ski and keep up with your proper routine and maintenance on it. There are times when any battery gets old will just no longer work, and it will have to be replaced.

Typically batteries on jet skis die sooner than other items as they get jarred around their whole working life. There are also times when your jet ski has been stored all winter and has not been started that you battery can just lose its charge and yes a jump start can get it started and going again, but there are safety issues that will need to be followed.

Things to Know about Jump Starting a Jet Ski

It is important to know that when you are jump starting a battery, that the charged battery will put the charge onto a dead battery.  Even though both batteries could be 12-volt batteries, not all have the same amperage. 

The higher amperage battery can dump the charge into the lower amperage battery and short out the electrical system on your jet ski and also do damage to the vehicle that the charged battery is in. Sometimes this has been known to cause your battery to explode, creating a safety hazard to anyone around, throwing battery acid everywhere. 

This can also cause sparks, and if there are any fuel vapors, this could cause an explosion.  It is recommended that the battery be removed from the jet ski and charged with a battery charger if you can instead of jump starting. We recommend charging before you take your jet ski to the lake if your jet ski will not start or your battery tests low.

Can You Use Your Vehicle or Boat to Jump Your Jet Ski?

It is not recommended to use your vehicle to jump your jet ski.  If you are at the lake and your jet ski will not start, that is what many people tend to do.  This can create issues for your vehicle and your jet ski.  If you choose this method in an emergency situation, make sure to follow certain steps to ensure safety and to protect your jet ski and your vehicle. If you are using a boat, there is no need to remove the PWC from the water.

  • Remove your jet ski from the water if the cables are not long enough
  • Know your vehicle’s battery carries more amperage than your jet ski’s
  • Do Not have your vehicle running when you try jumping your ski
  • Keep your jet ski close to the water, not letting it run long out of the water
  • Do not let your vehicle touch your jet ski

These are all particularly important things to know but we are not finished yet. Make sure that you have a long enough pair of jumper cables.  When connecting them, remember the red must always connect to the positive and the black to the negative on the charged battery.  Do not let the connectors on the ends of your jumper cables touch each other.

Hook up the connectors to your cable to the charged battery first.  Then carefully connect the positive or red cable to your positive post on your dead battery.  Connect the black cable or negative cable to a ground on your jet ski.  An engine bolt or metal part would also make a good ground.  Be as cautious as you can to make sure there are no gas fumes that could ignite and create an explosion.  

Once it is all connected, push the start button on your jet ski and hopefully it starts.  If not let it charge a bit more and try again.  Then get the jet ski immediately back into the water so not to damage the motor on your ski.  Be advised many of them will try to take off as soon as they are back in the water so jump on or hang on tight.  You must let your jet ski run to build your battery back up or you will have to repeat all of this again.

Jump Starting your PWC with a Free Standing Battery

It is highly recommended to use a free-standing battery versus using your vehicle.  It cuts down on some of the risks.  A free-standing battery is exactly what it says.  It means the battery is not connected to anything and stands by itself.  Make sure your free-standing battery has a full charge so that it will properly give a charge to your dead battery. 

You would follow the same steps and guidelines as jumping with a battery in your vehicle.  The dead battery will pull the amperage from the charged battery through your properly connected cables.  As always, use care when doing this and make sure your cables are properly connected and grounded.  As soon as your jet ski is started, let it run to charge your battery.  Of course, you must first disconnect the cables from both batteries and not let the ends of the cables touch.

Starting your Jet Ski with a Battery Booster

A battery booster is the safest way if you feel you must jump start your jet ski.  Even using a booster pack can create issues such as a defect or something is not right with the booster and it could fry your jet ski’s electronics. This is our favorite jump starter as it can retain its charge for a year and it comes with a tire pump in case you need to pump your vehicle or trailer tires on the side of the road.

Follow the instructions for the booster and your jet ski’s if there are any furnished.  You must first make sure that your booster is fully charged.  It is recommended to charge once monthly to make sure it’s ready to go.  If not, you can wait at the lake for it to fully charge with the use of a cord and your charging port or cigarette lighter in your vehicle. 

This is the same process as jumping using a battery: Hook the positive cable (red) to the positive post and the black to the negative or ground.  Once your ski has started, unhook your pack, and get your jet ski in the water. 

Best Way to Charge Your Jet Ski Battery?

It is not really recommended to jump start your jet ski, as you can see there are many things that can go wrong.  It is wise to always perform a maintenance check the day before you take it out on the lake.  When you are performing your checks, one of the important things that should be done is to check the amount of charge on your jet ski’s battery. 

Battery Charger

The best way to do this is to remove your battery from your jet ski and hook it to a battery charger that is plugged into an electrical out at your home.  Most of them will give you the reading of voltage and amperage that you battery is showing. Here is our favorite smart charger for PWC batteries.

If your battery is totally dead, it should recharge like this in about 2-4 hours.  If you do not have a smart charger, check your batteries progress about every half an hour so that it does not overcharge and fry your battery.  Then you must disconnect it and turn off your charger.

Smart Battery Charger

A smart charger is the best for many, this will automatically know when the battery is fully charged and will shut off by itself.  This protects your battery and your charger.  It is always wise to check on it yourself after a bit, just in case.  For the most part the smart charger will take care of everything for you.

Replace the Battery

If this problem of not starting continues, have your battery checked and replaced if need be. Here are our favorite batteries for PWC’s as well as a guide for trickle charging. You may have a parasitic drain as I have seen in some older Sea-Doo models which drain the battery in about a week of not riding, so that may be something to explore if you do have a newer battery.

If you have a parasitic drain, try installing a battery cut off switch to turn your battery of after every ride and it will be as good as new for the next outing.

It may also just be time to purchase a new battery.  If your battery checks out ok and your jet ski still is having problems starting, your problem is probably within your jet ski itself.  Even if you choose to try to jump start your jet ski, always be sure and follow all safety guidelines.

Can you jump start a seadoo with a car?

You can jump start a Seadoo with a car in an emergency situation, but it is not recommended. A car has more amps and can produce too high of voltage for jump starting a jet ski which in turn can fry the electronics. Always try and charge your battery to start your ski.