How to Winterize a Sea-Doo
- 1). Remove the plastic cover on the spark plug wires and, using your socket wrench, remove each spark plug, spraying DW40 or Sea-Doo brand fogging oil into the pistons, and replace the spark plugs.
- 2). Crank the engine to circulate the lubricant, and repeat the process once more.
- 3). Add fuel stabilizer to the gas tank to the appropriate ratio for the fuel remaining in the tank. Allow the engine to run for several minutes to circulate the fuel stabilizer.
- 4). Disconnect the battery. If you prefer, remove the battery entirely. If you remove the battery, store it in a dry space.
- 5). Clean and wax the exterior of your Sea-Doo and cover it for storage in a dry location.
Source...