How to Winterize a Jet Ski [A Step-by-Step Guide]

How to winterize a jet ski: We have owners asking us about this all the time. Responsible owners who live in an area of freezing winter temperatures, go beyond the regular maintenance tasks and add jet ski winterizing to their maintenance schedule.

Additionally, jet skis stored for the off-season in a warm climate also need to be prepared for long-term storage.  Finally, every jet ski needs to be “winterized” at a certain level, if they’ll be out of use for a while!

Would you like to know all the steps in this process?

These steps can vary a bit depending on the exact make and model, but the steps we’ve outlined here are basically universal.

Although our recommendations will help prepare your jet ski for the next season, we recommend that you refer to your owner’s manual because your jet ski’s manufacturer will have specific instructions for winterizing your make and model.

Keep in mind that the process of winterizing your jet ski does not replace its yearly service, which involves vital services like changing the oil and filters plus many other services that are spelled out in your owner’s manual.

If you are not mechanical at all, we recommend that you have your annual service and winterization done by your dealership or a reputable service shop. You can have both done at the same time after the season ends. This way you should be able to save time and money!

If you are skilled mechanically, you may want to do this yourself, in which case you should keep reading. You will also find out how to de-winterize a jet ski once winter is over!

We at JetDrift have compiled step-by-step instructions for you and found the best video guide available on the topic, and we’ve included that in this jet ski winterizing guide.

Do Jet Skis Need to Be Winterized?

Yes, every jet ski needs to be winterized to keep it in good condition for the next season and to avoid damage. Moreover, even if you live in a warm climate, you still have to prepare your jet ski for long-term storage! This prep process is nearly the same as winterizing a jet ski, so ultimately, you have to “winterize” your jet ski by all recommended methods if you won’t use it for a couple of months!

How to Winterize a Jet Ski

To winterize a jet ski, you need to take three important steps. 1. Fill up the tank, add stabilizer to the gas, then run the engine for two minutes. 2. Flush the systems with a (50:50) mixture of RV and water for another two minutes. 3. Lubricate the metal and moving parts. Finally, store the jet ski in a secure place properly.

While these are considered as the most important steps for jet ski winterizing, there are some other recommended steps for a more thorough winterizing.  For example, the majority of owners prefer to change the oil as part of the winterization process. Are you wondering why?

It’s because during the year, contamination and water may accumulate in the engine oil, which can cause damage or malfunctions. That’s why it’s recommended to change the oil at the end of the season.

The best practice is to winterize the jet ski and change the engine oil at the same time!  Additionally, you may want to inspect, clean, or even polish your jet ski before you store it for the winter months.

How to Winterize a Jet Ski, Step-by-Step

• Inspect the ski
• Fill up the gas tank, add fuel stabilizer and run the engine for 2 minutes
• Change the engine oil and the filter
• Create a mixture of one gallon of water and one gallon of RV antifreeze
• Flush the systems (cooling, exhaust, intercooler) for 2 minutes with this mixture
• Lubricate the metal and moving parts
• Remove the battery, store it properly, and attach it to a battery tender
• Clean, or even polish the jet ski carefully

In the next paragraphs, we’ll drill deeper into these steps one by one!

Carefully Clean Your Jet Ski

First of all, it’s recommended to clean your PWC carefully.

Pick up your garden hose and thoroughly rinse your entire jet ski. The footwells will be the dirtiest part. You will find a lot of dirt, grime and gunk stuck to them. A power washer should be used to thoroughly scrub it off.

Once you’ve thoroughly rinsed off your jet ski and it’s still wet, clean it with jet ski cleaner, which is a mixture of Simple Green and 50% water.

Spray your jet ski all over with the Simple Green and water mixture. Everything can be coated with it, even the engine. Make sure you spray on additional layers in the footwells.

Note: You only need to use the cleaning mixture if your jet ski is extremely dirty and this is needed in order to get it clean.

It’s now time to clean your seats. These need to be well taken care of because this is where you sit the entire time you are out at sea.

First rinse your seat off. Spray on some of the Simple Green mixture and start scrubbing with a brush. If you want your seats to really get clean, use a Magic Eraser.

The hardest part of cleaning your jet ski is finished. Now, all you have to do is dry it off. Take a soft clean white rag and use it to wipe down your entire craft. When the rag is drenched, ring it out and continue wiping.

Make sure you thoroughly dry the footwells. Once you’ve dried the entire jet ski, grab a new clean white rag and start all over. This will remove the little bit of water that remains.

Once you’ve finished using the second rag, grab some microfiber rags and polish the shiny spots, like the chrome and mirrors. If anything gets inside the hull, wipe it away, making sure the hull is completely dry as well.

Look over your jet ski one last time, making sure that it is totally dry. If so, you are now ready to tackle the last step in cleaning your jet ski.

Now that your jet ski is totally dry, grab bottle of spray wax and go over your jet ski with it. This will make it shine and give it a layer of protection against harmful elements in the environment.

If you need more information, there is a more detailed jet ski cleaning guide here.

Drain Your Jet Ski

The next thing you need to do to winterize your jet ski is to drain all the water out of your jet ski. (And you should do the same process after every ride as well!)

Immediately upon taking your jet ski out of the water once the season is over, we recommend that you drain all the water out of the exhaust and the cooling system. Most jet skis are cooled with anopen loop cooling system, which uses the cool lake or ocean water to lower the temperature of the PWC’s engine.

Water (especially salt water), which can corrode the engine if left for long periods of time, can contain substances like algae, sand, dirt and debris that can get trapped and muck up the parts. So, all this needs to be drained too.

Fortunately, you can drain it quite easily. Your owner’s manual will provide instructions, but for most jet skis, the process is basically the same.

Here’s how you do it:To drain the water, you first must position your jet ski for draining, so that the bow (front) is higher than the stern (rear). This way the water can drain out properly. You can do this by securing the jet ski in this position on the trailer.

Go back and forth with the throttle to drain the water out. Turn your jet ski on and in quick bursts, alternate back and forth with the throttle. To keep it from overheating, do it in 30-second intervals.

Keep doing this until the water has been drained from your jet ski. And, don’t forget to remove the drain plugs so the bilge water can drain out!

Flush with Antifreeze

It is extremely important that you thoroughly flush your systems with antifreeze. Do not skip this step!

Even though you’ve completely drained the water out of your jet ski, there may be some water remaining in the systems. When water temperatures drop to freezing, it will turn to ice and expand. This can break parts in the engine. This is why you have to be so cautious about any water left in during the winter in freezing weather.

To prevent engine damage, you need to use antifreeze to flush your cooling system once the season is over. This must be done before freezing weather! This will not only clean the system out but will also protect it from any potential damage due to expanding water.

Here’s how you do it:You mix water with antifreeze in a large bucket. Do not use standard automotive antifreeze, but RV antifreeze instead because it won’t harm the environment as much.

The antifreeze will keep any fluids in the exhaust system from freezing while your jet ski is being stored for the winter. Mix 1 gal. (3.8 L) of RV antifreeze with 1 gal. (3.8 L) water in a 5 gal. (18.9 L) bucket.

Flush this mixture throughout the entire cooling system with a waterpump. You can connect a hose to the flush connector and keep the other end submerged in the mixture. Keep turning the engine on and off after the mixture is finished going through the system.

For Closed Loop Cooling Systems

If your engine is cooled with a closed loop cooling system, the closed system is already filled with liquid antifreeze. So, there is no need to thoroughly flush the cooling system.

You just need to use a hydrometer to check how strong the antifreeze/coolant is. If you need to drain it (need to be replaced after every 200 hours or 2 years!), use the drain cock on the radiator, then fill it up with the right coolant.

But you need to be careful!

Although your cooling system is closed loop and already filled with liquid antifreeze, your intercooler and exhaust systems still get cooled by regular water!

This means the intercooler and exhaust systems must still be flushed out with the antifreeze mixture.

Again, refer to your owner’s manual for the exact instructions so that you can be sure that you’re thoroughly flushing out your systems!

Fill Up Your Gas Tank & Use Stabilizer

The next step in the jet ski winterizing process is to fill your gas tank up completely to the top and you need to add stabilizer to the gas.

Now run the engine at 30-second intervals. This will ensure that the stabilizer reaches all the important parts of your engine. This will keep the fuel from becoming contaminated and prevent a buildup of residue in the fuel injection system or carburetor, as well as the gas lines.

A lot of owners just drain their jet ski, fuel it up, and take out the battery as their winterization process. But that’s not really enough. If you want to learn how to winterize a jet ski thoroughly and properly, keep reading because there’s quite a lot to this.

Lubricate the Moving Parts in Your Jet Ski

Once you’ve stabilized your fuel, it’s time to lubricate all the cables and seals with the spray lubricant and protectant that your jet ski’s manufacturer recommends.

While you’re spraying the lubricant, focus on the areas that turn and rotate all the time. These would be the pivot points on the steering nozzle, the brake and reverse mechanisms and more. You should also spray the engine with lubricant and the electrical components to get rid of any water that may remain.

Refer to your owner’s manual so that you make sure you are lubricating all the areas recommended by your manufacturer before storing your jet ski for the winter.

Remove, Charge & Store Your Battery

In time all batteries will lose their charge. This means you need to remove your jet ski’s battery and fully charge it while your jet ski is being stored. Before you take the battery out, first remove the negative connection, and then remove the positive connection.

Once the battery has been removed place it on a stable surface away from anything that could catch fire. Hook the battery up to an automatic battery charger. Also, you need to perform this task in a place where the temperature will not go below freezing.

Jet Ski Winterization and the Annual Service

Keep in mind that winterizing your jet ski does not replace its annual service!

The annual service usually involves changing the oil in the engine and changing the filter, removing the prop and the grease prop shaft, replacing the spark plugs and other tasks listed in your owner’s manual. If you do not know how to service your jet ski yourself, take it to your dealership or a reputable jet ski service ship so that the professionals can handle it.

But if you are an experienced mechanic with the proper tools, you should be able to handle the annual service yourself. If you want more information on doing the yearly service or how to winterize a jet ski, we recommend that you watch the following video on how you can accomplish both of these services at the same time.

Remember that the steps to properly perform these services may vary depending on the model, so you must see what your owner’s manual has to say on the subject so that you don’t make mistakes.

The Final Steps in Jet Ski Winterization – Storage

The perfect place to store your jet ski would be on its trailer parked in your garage or some other safe and secure spot. But if you don’t have room in your garage, you may store it in a barn or shed on your property, or perhaps outside.

Just make sure you store it away from anything that could catch fire because the gas tank is full.

We recommend that you store your jet ski on the trailer or even on a dolly. If you’re going to store it on its trailer for a long period of time, you need to slightly deflate the tires before putting the trailer up on wooden blocks or jack stands.

Also, put something noninvasive in the exhaust pipe to keep small animals or insects from going in there. You may not think this can happen when the jet ski is covered, but it does!

Remove anything valuable that may be in storage areas, especially expensive electronics.

Last but not least, you need to properly cover your jet ski so that it stays protected, either with its fitted cover or a tarp. If you’re going to store it outside, in a shed or barn on your property, you should give it a little more protection by covering it with a second cover or tarp.

It’s also important that you insure your jet ski, even when it’s in storage.

How do You Winterize a 2-Stroke Jet Ski?

You can winterize 2-stroke jet ski in the same way as a 4-stroke jet ski, except that there is no need to change engine oil in it, of course. Additionally, many owners prefer to “fog the engine” while they winterize their 2-stroke jet skis. Fogging the oil simply means to spray engine fogging oil into each carburetor’s throat as well as into the cylinders directly after you’ve removed the spark plugs.

How Do You Store a Jet Ski for the Winter?

To store your jet ski perfectly for the winter, put the cover on and move the trailer/dolly to a dry and secure place. It’s highly recommended you store your jet ski indoors for the winter months! Additionally, make sure that the hull is in a horizontal position and that you’ve removed all of your valuables from the storage compartments.

How Much Does it Cost to Winterize a Jet Ski?

If you do it by yourself, winterizing a jet ski costs as low as $25, as all you need is a fuel stabilizer ($10), a lubricant spray ($10), and one-gallon RV antifreeze ($5). If you change the oil and the filter as well, this would cost an extra $30-$70. If you get it done by a professional, winterizing a jet ski may cost you around $150-$300, not including the oil change!

What Happens if You Don’t Winterize Your Jet Ski?

If you don’t winterize your jet ski properly, it may end in serious damage. If raw water remains in the cooling system, exhaust system or the intercooler, the expanding ice can damage these parts which can result in costly repairs. Moreover, other metal parts or even the engine internal parts may begin to rust due to lack of lubrication or oil change. Finally, the fuel can go bad clogging the fuel line and injectors or carburetors.

How to De-Winterize a Jet Ski

After reading this detailed guide on how to winterize a jet ski, you probably want to know how to properly de-winterize a jet ski because when winter ends, you’ll want to take your jet ski out again.

You’ll be happy to learn that de-winterizing is a much easier process.

Reinstall the Battery

If you winterized your jet ski correctly, you removed the battery and hooked it up to an automatic charger to keep it charged throughout the winter. Before hooking it back up to your jet ski, make sure it’s got a fresh full charge.

First, disconnect the charger from the battery. Check the charge on the battery and if it stays over 12 volts, it’s fine. You can now reinstall it into your jet ski. If it’s been charged but it’s still dead, you need to buy a new battery.

Reinstall the battery by first reconnecting the connectors. Do the positive lead first and then connect the negative lead. You also need to remember to connect the vent hose.

Then, check all your fluid levels. Look for any possible leaks in the engine compartment. If it’s clean then it’s safe to start your jet ski, for 30 seconds max. Don’t be alarmed if the fogging oil causes some smoke.

Tighten Things Up

Thoroughly examine all cables, wires and belts. You are looking for any damage, indications of wear and tear, cracks and anything loose. Anything that looks worn or damage should be replaced and make sure that everything else is properly secured or tightened.

You also need to inspect the trailer and don’t forget to re-inflate the tires!

Next, put all your safety accessories back in the jet ski. These include your air horn, anchor, fire extinguisher, flashlight, paddle, and etc. If you do not have all the required safety accessories, you should get them now so that you remain safe and legal.

Fortunately, you can obtain everything you need in a single set:

Conclusion – Why Should You Winterize a Jet Ski?

As you’ve learned, you have to winterize your jet ski to keep it in good condition and avoid costly damage caused by expanding ice. Don’t forget that even if you live in a warm climate, you have to prep your jet ski for long-term storage if it won’t be used for a while!

After your last jet ski ride of the season, it is essential that you take the time to winterize your jet ski so that it functions properly when you try starting it up for next season.

Refer to your owner’s manual and follow the steps outlined above in our guide if you want to find out how to winterize a jet ski properly. In addition to your jet ski’s annual service, this would be the most important maintenance step if you want your craft to be in good working order for the next season.

Again, if you plan on winterizing your jet ski yourself, you must refer to your owner’s manual and follow those instructions. This is the only way to be sure that you’re doing everything that your manufacturer says is required.

If you have doubts about doing this yourself, you can get it done at the same time your jet ski is having its annual service at your dealership or a reputable service shop (or you can even call a mobile jet ski repair service). It would definitely be worth the cost to get it done properly.

Winterizing your jet ski will ensure that it stays in great condition for many years to come and keep it from being unnecessarily damaged.

We hope that you found our guide on how to winterize a jet ski interesting and helpful!

*Disclaimer: This guide is not intended to take the place of professional recommendations from your jet ski dealer or service provider. The required maintenance and winterizing process may vary from model to model. You need to refer to your owner’s manual for the instructions that specifically apply to your jet ski brand, model, and year.