How to Winterize (Or Un Winterize) a Jet Ski

If you live in an area that experiences harsh winters, then you know how crucial it is to protect your motor-based gadgets. Winterization is the process of preparing your electrical tools and gadgets for winter to prevent them from being damaged by the freezing temperatures.

The damage occurs when freezing temperatures change the composition of fuel in your engine, causing it to corrode your engine as well as other parts of the motor. Or when freezing of water in the pipes or other parts of the gadget—causing the pipes to crack due to water expansion. This will cause your gadget to stop working.

As such, winterization is critical as it saves you from having to spend money to repair your lawnmower, air compressor, or even jet ski come summertime. And it is actually easier than it sounds. Here are some easy steps you can use to winterize and de-winterize your jet ski.

How to winterize a four-stroke engine jet ski

Items needed:

  • Water and hose
  • 5-gallon bucket
  • Premium gasoline
  • Jet ski trailer or wave runner storage dolly
  • Non-detergent boat soap
  • Clean towels/scratch-free car wash rags
  • Silicone lubricant spray
  • Fogging oil spray
  • 50/50 Water and Antifreeze mixture
  • Rust inhibitor spray
  • Automatic battery charger + maintainer
  • Fuel stabilizing fluid
  • Marine Wax
  • Electric waxer or waxer drill attachments
  • Soft lint-free cloth for waxing
  • Jet ski cover

Winterization steps:

  1. To be able to tow your jet ski easily and prevent it from freezing, place it on a trailer or dolly before you start the winterization process.
  2. Then raise the front part of the jet ski so that it is tilted for easier water draining. The bow of the jet ski should be higher than the stern.
  3. Then proceed to remove the drain plugs so you can empty the hull.
  4. Turn on the jet ski and throttle it in short bursts so the jerking motions can help to drain all the water from the hull. Do this in 30-second intervals to prevent overheating.
  5. Remove the spark plugs from the engine and spray fogging oil into each cylinder. Then turn the engine on with the starter while the plugs are still out.
  6. Alternatively, you can spray fogging oil into the throttle body while the engine is running until the engine stops. For more clarification, refer to your jet ski’s manual.
  7. Then wash the engine thoroughly to remove all oil with soap and water.
  8. Then drain the hull entirely and replace the drain plugs.
  9. Next, mix antifreeze designed for use in jet skis with water at a ratio of 1:1. Do not use car antifreeze.
  10. Flush the antifreeze mixture through the exhaust system. This will prevent any water in the exhaust from freezing and causing the exhaust pipe to crack. You can use a pump, but the raised position will cause the antifreeze to move through the exhaust system using gravity.
  11. Then add a fuel stabilizer into the gas tank to prevent residue formation in the fuel injector, carburetor, and gas line.
  12. Then fill up the gas tank completely. To eliminate any room for condensation, which can damage the gas line and the engine.
  13. Wash the exterior of the jet ski and dry it thoroughly. Then wax it until it is shiny.
  14. Finally, lubricate the control cables, steering system, engine, and other moving parts of the jet ski.
  15. Remove the battery and store it indoors in a fairly warm place to prevent draining over winter. Remember to charge it until it is full before storing it.
  16. At this point, you can go ahead and use the Rust inhibitor spray on any parts of the jet ski that may be prone to rust. To prevent them from rusting, should snow or condensation get onto the jet ski.
  17. Wipe down any other parts of the jet ski, such as the seat, to prevent mildew formation. You should also keep your seat slightly unlatched for air circulation.
  18. Then cover the jet ski with the jet ski cover and move it into your garage or stage unit.

 How to winterize a two-stroke engine jet ski

Items needed:

  • Water and hose
  • 5-gallon bucket
  • Premium gasoline
  • Jet ski trailer or wave runner storage dolly
  • Non-detergent boat soap
  • Clean towels/scratch-free car wash rags
  • Silicone lubricant spray
  • Fogging oil spray
  • 50/50 Water and Antifreeze mixture
  • Rust inhibitor spray
  • Automatic battery charger + maintainer
  • Fuel stabilizing fluid
  • Marine Wax
  • Electric waxer or waxer drill attachments (optional)
  • Soft lint-free cloth for waxing
  • Jet ski cover

Winterization steps:

  1. Start by placing the jet ski in a tilted position while on the trailer for easy draining.
  2. Wash the jet ski to remove any algae or grime from the lower part of the jet ski.
  3. Add a fuel stabilizer to the gas tank after filling the tank with premium fuel.
  4. Then run the jet ski engine for at least ten minutes to allow the stabilized fuel to run through the entire gas line system.
  5. Flush the port with clean running water to remove any salty or contaminated water from the port.
  6. Ensure you turn on the engine before turning on the water and shut off the water first before turning the engine off.
  7. Proceed to remove the jet ski battery and charge it completely before storing it in a fairly warm place.
  8. Spray the moving parts with silicone lubricant and the metal parts with anti-rust spray.
  9. Fill up the oil tank to eliminate condensation space.
  10. The freeze-proof the exhaust using the anti-free mixture. Use RV antifreeze as it is environmentally safe.
  11. Remove the jet ski engine’s intake cover and spray fogging oil spray into the engine. Use enough spray to cover the intake valve, crankshaft, crank bearings, and reed valves.
  12. Remove the spark plugs from the engine and check compression readings. Make sure the spark plugs are grounded when checking compression.
  13. Then proceed to fog the engine by turning on the engine and letting it turn off once it is completely fogged.
  14. Spray fogging oil into the spark plug holes. Then reinstall the spark plugs.
  15. Dry the jet ski completely and wax it until it is fully coated and shiny.
  16. Then cover the jet ski in a jet ski cover and store it as planned.

How much antifreeze do I need to winterize my jet ski?

It depended on your jet ski size. But most people use roughly 5 gallons of antifreeze mixture to flush their jet skis. As a rule of thumb, use 50% antifreeze and 50% water to make your antifreeze mixture. It is best not to be frugal with your antifreeze as it plays a significant role in ensuring costly parts of your jet ski are not damaged by winter cold.

What happens if you don’t winterize your jet ski right?

Failure to winterize your jet ski can lead to engine or motor damage, which may end up costing far more than the resources and time you would have used to winterize your jet ski. It may also lead to exhaust system damage and damage of other parts such as the gas tank and gas lines.

It is far more expensive to repair your jet ski engine than it is to buy an antifreeze, silicone lubricant, and gas stabilizer. And spend a couple of hours draining, cleaning, replacing gas, lubricating, and storing your jet ski correctly.

How much does it cost to winterize a jet ski?

If you intend to have it winterized by a mechanic, it may cost you roughly $600- $800. This cost may vary from state to state. Be sure to call your local mechanic to get an accurate figure. On the other hand, if you do it yourself, the only cost is the cost of the gas, soap, fogging oil spray, marine wax,

How do you un-winterize a jet ski?

Once winter is over, you will need to follow some steps to prepare your jet ski for use. Unlike the winterization process, this process entails the inspection of various parts of the jet ski. Here are the main things you need to inspect before ferrying the jet ski to the water for some fun time.

Items needed:

  • Engine oil
  • Oil filter
  • Battery tester
  • Fuel filter
  • WD-40
  • Drain plug
  • Spark plugs

De-winterization steps

Check 1: Oil Check

Check the oil in the engine and change it as well as the oil in the outdrive. You can also change the oil filter at this point as part of your annual jet ski maintenance.

Check 2: Battery Check

Reinstall the battery and check to see if it has water. Fill it up if necessary. Then check the battery voltage and amps using a battery tester.

Check 3: Fuel Check

Inspect the fuel tank and line to ensure they are still working correctly. Change the fuel filter and check the pipes for cracks. Test the oil to see if it is useable and change it if it has been diluted by moisture or condensation.

Check 4: Engine Check

Replace the spark plugs and check to see if the distribution cap needs cleaning. Make sure all connections are intact. Inspect the belts and tighten them if they are loose. Then replace any worn out alternator belts. Then lubricate the engine with WD-40 and insect the rudder and the engine shafts.

Check 5: Exhaust Check

Then check the exhaust system and the cooling system to see if any of the pipes may have cracked due to water expansion. Rinse out the strainer in the cooling system to remove any debris. Then inspect other hoses in the jet ski to see if they have any cracks.

Check 6: General Check

Finally, inspect other jet ski parts such as the trim, VHF radio, horn, power steering, cables, and bilge pump. Once you have ascertained everything is working as expected, you can tow the jet ski to the water and use it.

Key reminders

Always refer to your jet ski manual to confirm the exact steps you should take when winterizing and de-winterizing your jet ski. When removing your battery, remove the negative connection first before removing the positive one.

And finally, take advantage of the de-winterizing inspection and work on other issues affecting your jet ski to ensure it will work properly all summer.