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How To Winterize a Sea-Doo [ A Step-by-Step Guide]

How To Winterize a Sea-Doo [ A Step-by-Step Guide]

Winterizing your Sea-Doo is an important part of its yearly maintenance.

It’s imperative to keep your craft in good shape and avoid damage during the winter months.

It’s also good to know that even if you don’t live in a cold climate, you still have to prep your Sea-Doo for the off-season!

If you’d like to know how to winterize a Sea-Doo properly, this post is for you. We, at JetDrift, set up a step-by-step guide on how to do this process by yourself!

Do You Need to Winterize Your Seadoo?

Since Sea-Doos are cooled with a closed-loop cooling system, there are many rumors and a lot of false information out there about its winterization.

Many believe that Sea-Doos don’t need to be winterized, but they’re wrong!

Contrary to popular belief, every Sea-Doo needs to be winterized before the off-season. Although Sea-Doos don’t use external water to cool their Rotax engines, their exhaust and intercoolers are still cooled with raw water. That’s why it’s important to flush your Sea-Doo with antifreeze before the winter. Moreover, winterization is much more than protecting the systems from the expanding ice, as it includes stabilizing the gas, lubricating the moving parts, and many other important steps. 

This means even if you don’t live in the northern climates, you still have to prepare your Sea-Doo for the off-season!

How To Winterize a Sea-Doo

To winterize a Sea-Doo properly, you have to add stabilizer to the gas first and fill up the tank completely. Then you have to flush the exhaust system with antifreeze and when it’s done, drain the liquid completely. Additionally, lubricate the moving parts, remove the battery and store it properly for the winter months. Finally, it’s recommended to clean the Sea-Doo carefully and store it in a secure place.

When it comes to Sea-Doo winterization, it’s very important not to confuse its periodical maintenance with winterizing!

In most cases, it makes sense to do the required yearly maintenance and winterization at the same time after the end of the season.

If you’d like to learn more about required Sea-Doo maintenance, don’t miss our detailed post on the topic.

In this post, we’ve also included the most common yearly maintenance steps, like oil or coolant changing.

But be aware that depending on your Sea-Doo’s type and engine hours, additional maintenance like supercharger rebuilding may be required!

That’s why you have to refer to your owner’s manual before you service and winterize your Sea-Doo!

Step-By-Step Sea-Doo Winterization Guide

Before you start the process, it’s highly recommended you read the owner’s manual carefully, or consult with your dealer, since the necessary tools and steps may vary from one Sea-Doo to the next.

Step 1 – Inspection

It’s important to check your Sea-Doo before you start the winterization process, just like you should inspect it each time before you ride. You may want to check the hull, the dashboard for fault codes, the engine compartment for leaks, and loosened connections.

It’s recommended you inspect the fuel-, cooling-, and air intake systems, as well as the pump. Also, never overlook the supercharger and the carbon seal!

Step 2 – Fill Up the Tank and Add Stabilizer

Before you start to winterize your Sea-Doo, you have to fill up the fuel tank completely and you also have to add stabilizer to the gas.

This is necessary as gas can go bad in just a couple of months, which may result in contamination in the fuel line, clogging the injectors (or carbs).

To prevent this, add the right amount of stabilizer to the tank, fill it up with fresh gas and run the engine for maximum 2 minutes while it’s attached to the garden hose.It’s necessary as the stabilized fuel has to reach the injectors or carbs.

Step 3 – Change Engine Oil

If you have a 4-stroke Sea-Doo, you should change the oil and the filter as part of the Sea-Doo winterization process.

Are you wondering why?

The reason is that it’s always wise to store your Sea-Doo with fresh oil for the off-season. Used oil in the engine contains some contamination and water (yes, really – due to absorption), which can cause rusting and other damage in the internal parts of the engine.

You can learn how to change the oil in your Sea-Doo properly from this detailed step-by-step guide.It’s recommended you change the engine oil before you flush the exhaust with antifreeze, as you’ll have to run the engine after changing the oil.

Beyond the oil change, don’t forget that you have to inspect the spark plugs every year, and replace them every 2 years (or 200 hours).

Also keep in mind that you probably have to rebuild the supercharger after 100 engine hours, or every 2 years.

Step 4 – Check the Coolant

The Sea-Doo’s closed-loop cooling system is filled up with a special liquid, known as coolant.

The manufacturer recommends checking the coolant every year (or after 100 engine hours) and replacing it every 2-5 years depending on the model. For exact service intervals please refer to the manual.

Step 5 – Flushing With Antifreeze

Flushing the Sea-Doo with antifreeze is probably the most important step on this list.

Although Sea-Doos use a closed-loop cooling system, their exhaust system and the intercooler on the supercharged models are still cooled with external water! 

Because of this, you have to flush these systems first with fresh water to remove potential contamination like sand, debris, etc. from the systems.

To do it properly, attach a garden hose to the flushing connector, start the engine first, and only after that turn on the water. Run the engine for a maximum of 2 minutes at idle speed, stop the water first, then shut off the engine.

Rinse down the pump, iBR (braking system), and the intake grate from the outside with the garden hose.

Then, you have to flush the exhaust again, but with a mixture of water and antifreeze. To create this mixture, you should mix 1 gallon of non-toxic RV antifreeze with 1 gallon of water in a bucket.

Connect a hose to a water pump or bilge pump, as you’ll need a little pressure to force this mixture into the exhaust system.

Attach the hose to the flush connector and flush the system again with this mixture as described above.

Once it’s done, “blip the throttle” just a little to drain the exhaust system completely.

Step 6 – Lubricate the Moving Parts

Lubricate the moving parts and the metallic components in the engine compartment, in the pump, and in the iBR to prevent corrosion.

Sea-Doo recommends using the XPS Anti-Corrosive Lubricant, but other marine lubricant sprays are also suitable.

Step 7 – Battery Maintenance

When you’re winterizing your Sea-Doo, you have to pay attention to the battery, too.Contrary to popular belief, you have to remove the battery from the Sea-Doo and store it in a cool and secure place. The best practice is to hook it up on a battery tender to keep it charged during the winter months.

Depending on the type of the battery, it may also need maintenance. The best Sea-Doo batteries are the maintenance-free AGM sealed models.You may want to know how to remove a Sea-Doo battery, and how to charge it properly.

Step 8 – Cleaning

Before you store your Sea-Doo for the winter months, the best practice is to clean it perfectly.It’s also wise to make sure that the bilge is completely dry before you store your Sea-Doo for the winter. Moreover, you can consider polishing it to restore its original shine.

Step 9 – Storage

Finally, you have to cover and store your Sea-Doo properly.Whether you store it in your garage or another location, make sure it’s in horizontal position, and pay attention to the security as well.

Additionally, remove your valuables from the storage compartments, especially your cameras, GPS, VHS radio or other electronics.

How To Winterize a Sea-Doo Spark

To winterize a Sea-Doo Spark, you have to remove the top deck first. It ‘s not only tricky, but you’ll also need the help of a friend to lift the deck. Once you’ve removed the top deck, you can winterize a Sea-Doo Spark just like any other four-stroke Sea-Doo model.        

To remove the deck, you have to remove around 30 bolts and nuts then disconnect the electrical connections, and the steering cable.

You can see this process as well as the complete Sea-Doo Spark winterization process in this tutorial video:

How To Winterize a Sea-Doo Jet Boat

Sea-Doo jet boats can be winterized in the same way as any Sea-Doo personal watercraft. This is because all of these vessels are powered with the same Rotax engines. Be aware that older Sea-Doo jet boats (before 2006) are powered with 2-stroke engines, thus you don’t have to change the engine oil when you winterize it.

Why it’s Important to Winterize a Sea-Doo

It’s important to winterize a Sea-Doo because raw water may remain in its exhaust system or the intercooler, which can expand as a result of freezing. This expanding ice may end in serious and costly damages! Additionally, other steps like stabilizing the fuel, lubricating the metal parts or charging the battery are also important parts of the process to keep your Sea-Doo in good shape for the next season.

How Much Does it Cost to Winterize a Sea-Doo?

It costs around $25 to winterize a Sea-Doo if you do it yourself excluding oil change ($5 -RV antifreeze, $10 – lubricant spray, $10 – fuel stabilizer). If you get it done by a professional service shop or an authorized dealer, it can cost up to $150-$300 to winterize your Sea-Doo. Be aware that the labor costs vary widely depending on the shop’s location!

Moreover, professionals usually offer full maintenance service that includes winterization as well as the yearly mainenance, which includes the oil and filter change, coolant change, supercharger rebuilding, and all else that is needed.

The complete yearly maintenance of your Sea-Doo may cost around $300-$1,000+ depending on the model and its condition. It’s good to know that just rebuilding the supercharger costs around $500, and it’s necessary every second year (or 100 engine hours) on most models!

On the other hand, if you change the oil and the filter by yourself, it costs an additional $35-$70, even if you choose the Sea-Doo oil change kits.


You have to winterize your Sea-Doo at the end of the season to avoid damage and malfunctions. Even if you live in a warm climate, you have to prepare your Sea-Doo for the off-season!

A thorough Sea-Doo winterization process should include these following steps:

  • Inspect the Sea-Doo carefully
  • Add stabilizer to the fuel
  • Fill up the fuel tank completely
  • Change the engine oil and filter
  • Check the coolant and replace if needed
  • Flush the exhaust system with fresh water for 2 minutes
  • Create a 50:50 mixture of water and antifreeze
  • Flush the exhaust system with the mixture for 2 minutes
  • Lubricate the moving and the metal parts
  • Remove the battery and attach a battery tender to it
  • Clean the Sea-Doo carefully
  • Store it properly and securely in horizontal position
Although an oil change is not considered part of the winterization process, it’s highly recommended to change it at the end of the season. The best practice is to do both at the same time!

It’s because contamination and water (due to absorption) can accumulate in the engine oil during the season, which can lead to damage and malfunctions in the engine.

Because of this, always store your Sea-Doo for the winter months with fresh oil!

When you do it by yourself, winterizing a Sea-Doo costs as low as $25, as you’ll only need a lubricant spray, a gallon of RV antifreeze, and a small amount of fuel stabilizer.

If you change the oil as well (which is recommended) be prepared for an additional $35-$70 extra cost.

Winterizing a Sea-Doo could be much more costly if you get it done by a professional, so be prepared to pay around $150-$300 without the oil change!

Don’t forget, that beyond winterizing and the oil change, other maintenance may be required on your Sea-Doo, such as changing the coolant or rebuilding the supercharger.

That’s why you should refer to the owner’s manual at all times!