10 Steps to Winterize a Jet Ski

Oh no! The days are getting colder and it is time to put away your SeaDoo or Yamaha jet ski until next year. If you live in a warm climate, perhaps you can simply keep your jet ski in a wet dock and “winterizing” is more a figure of speech; however, if you live in a state where the temperature drops are drastic and include freezing weather, your jet ski will require full winterization and storage. Your model’s manual will be your best friend when it comes to detailed instructions for some winterizing procedures, but for a quick overview, look no further!

Empty out your gear from the storage compartments

As you prepare for winterization, take this opportunity to clean out your storage compartments. Take out the towels, toys, and other items and give each compartment a thorough wipe-down to make sure they are clean and dry. Consider leaving them slightly cracked to prevent moisture from getting trapped, and think about throwing in a dryer sheet or peppermint spray on a rag to deter animals from nesting.

Drain out leftover water

Because jet skis use the water they are in as a way to cool their system while the engine is running, it’s important to make sure all of that liquid is removed before storage. Moisture is the bane of stored vehicles, and jet skis are no exception. Tilt your jet ski up at the front so that gravity doesn’t work against you. You can do this on a boat ramp, a jet ski lift, or lift the front using materials lying around your garage. Start it up and leave it running for 30 seconds, turning the throttle periodically. Turn it off, then repeat the process a couple of times until no more water comes out.

For colder climates: Run anti-freeze through your system

If you live in an area with winters that reach below freezing, and if you’ll be storing your jet-ski outside, running anti-freeze through your system prevents any leftover moisture from expanded and cracking its surroundings as the temperature drops. Mix 1:1 water and RV anti-freeze in a 5-gallon bucket, place a hose or water pump in the flush outlet and put the opposite end in your solution. Then, turn the engine on and off until the mixture has passed through the exhaust system.

Thoroughly clean the outside

If you live in an area with winters that reach below freezing, and if you’ll be storing your jet-ski outside, running anti-freeze through your system prevents any leftover moisture from expanded and cracking its surroundings as the temperature drops. Mix 1:1 water and RV anti-freeze in a 5-gallon bucket, place a hose or water pump in the flush outlet and put the opposite end in your solution. Then, turn the engine on and off until the mixture has passed through the exhaust system.

Stabilize & top up your fuel

Always store your jet ski with a full tank to prevent condensation from forming on any exposed surfaces within your fuel system. Add a stabilizer, then run the engine in 30-second intervals so that it mixes in with your fuel. This will reduce the risk of your fuel breaking down, especially if you’ll be storing your jet ski for a long period of time.

Lubricate seals, cables and exposed parts

Lubricate all seals and cables using a lubricant and protectant recommended by your jet ski’s manufacturer, or one that you know to be safe. This will coat the parts so that water cannot corrode or otherwise compromise them during storage.

Spray fogging oil in the carburetor and spark plugs

Remember how we don’t like moisture? Fogging oil coats important parts so that moisture can’t settle on them and cause corrosion. Remove the air filter on your jet ski, then spray the carburetor and spark plug cylinders with fogging oil. The best way to tackle this is to turn on the engine and spray it down while the engine in idling, until the engine stalls.

Remove your spark plugs, and spray fogging oil into each hole for a couple of seconds. Then place a rag over the holes and turn on the jet ski so that the oil coats the internal parts without spraying oil everywhere. The engine most likely won’t turn start at this point, and that’s ok. Don’t forget to pop the spark plugs and the air filter back in when you’re done! This step also allows you to check your spark plugs and note if any need to be replaced next season.

Remove the battery & store it safely

The battery will most likely drain over time if left in the jet ski. Disconnect the negative terminal, then the positive terminal, and store it in your garage or another location that won’t get below freezing. Putting it on a trickle-charge is recommended, and never store a battery directly on concrete – place it on a mat, or on another raised surface

Prevent critters from finding a new home

Cover the exhaust to prevent bugs and critters from crawling up there in search of a safe, protected home for the winter. There are plenty of materials to choose from – steel wool, dryer sheets, and similar material will both deter and provide a physical barrier to prevent those little suckers from creeping in and building nests.

Cover & store your jet ski in a secure location

For easy maintenance, store your jet ski on its trailer. Take the trailer wheels off to prevent flat spots and dry rot as it will be sitting for some time. No matter where you choose to store it, covering the jet ski is a must. Whether it’s a tarp or bona fide jet ski cover, it will prevent dust and dirt from settling in the cracks and crevices during storage. Never store your jet ski in your house, as it will emit fumes (it’s full of gas, after all!).

These basic steps will keep your jet ski stored safely until it’s time to de-winterize it and get it back into the water. Before starting the winterization process, please be sure to double-check with your PWC’s manufacturer manual to see if there are model-specific steps that need to be included.