How To Winterize Your Boat and Trailer

Learn how to winterize a boat.

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Next Project

An hour or less






You've had a blast on the boat with family and friends all summer, but now it's time for all that water fun to end. If you want to repeat the good times next year and protect your engine during the cold winter months — thus minimizing early season startup problems — read on.

Note: This how-to features an inboard 1999 Bayliner 2050ss Capri stored in Northwest Arkansas, a freshwater environment where the winters rarely get below -10 F. For colder climates, the process is similar, but should incorporate an antifreeze that can stand up to the typical winter temps there.

Consider this a general overview of the process. Every boat is slightly different, every climate has unique requirements and saltwater and freshwater situations require different steps.

Tools Required

  • Battery charger
  • Cleaning rags
  • Flashlight
  • Flathead screwdriver
  • Garden hose
  • Motor flusher engine muffs
  • Thin piece of wire
  • Work gloves
  • Wrench

Materials Required

  • Antifreeze
  • Boat cleaner (any multi-purpose cleaner will work)
  • Fogging oil
  • Fuel stabilizer
  • Gasoline
  • Marine grease
  • Rags

Project step-by-step (11)

Step 1

Set Up Your Workspace

Boat In Garage irina88w/Getty Images

Step 2

Locate the Drain Plugs

Drain plugs can be challenging to find, so make sure to do this before diving into the winterization process. Plus, if the boat engine is hot, it will make feeling your way around unsafe.

  • Pinpoint exactly where the drain plugs are, using the owner’s manual or some online research.

Locate the Drain PlugsYoon Kim for Family Handyman