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Winterization

Get tips on Winterizing your boat Winterization checklist to help with winter storage Shop Short Haul Products
Antifreeze

Antifreeze

Winterizing Kits

Winterizing Kits

Boat Stands

Boat Stands

De-Icers & Aerators

De-Icers & Aerators

Fuel, Additives & Engine Treatments

Fuel, Additives & Engine Treatments

Oil Changers

Oil Changers

Oils, Lubes & Systems

Oils, Lubes & Systems

Moisture Control

Moisture Control

Cabin Heaters

Cabin Heaters

Shrink  Wrap, Tools & Supplies

Shrink Wrap, Tools & Supplies

Engine Flush

Engine Flush

Buoys & Winter Sticks

Buoys & Winter Sticks

Boat Covers

Boat Covers

Cover Supports & Tarps

Cover Supports & Tarps

Bilge & Engine Heaters

Bilge & Engine Heaters

Dr. Shrink Instructional Videos

Everything Needed to Shrink Wrap

How to Shrink Wrap a Small Powerboat

How to Shrink Wrap a Sailboat

How to Shrink Wrap a Pontoon Boat

Tips for Winterizing Your Boat

If you're looking for advice on how to winterize your boat and engine, check our Top Winterizing Tips (pdf) to help you get started. Defender stocks a variety of products, from antifreeze, oil changing kits and fuel additives, to boat stands, cabin heaters, boat covers, shrink wrap and more for winterizing a boat of any size and style. We stock winterization kits to help you protect your onboard plumbing, such as potable water supplies, waste water systems, raw water cooling systems and more. In addition, we carry a wide variety of items to help control moisture and condensation in the boat cabin to dehumidify and prevent mold and mildew. Defender also carries an assortment of products to help you flush and winterize your outboard, inboard, or inboard/outboard (I/O) engine, including oil changers, engine flush systems, fogging oils and fuel stabilizers. Use our Winterizing Equipment Checklist (pdf) to ensure that you get all of the products you need to winterize your boat.

Defender's Boat Winterizing Kits

Properly winterizing your boat is essential to its long-term survival. The same goes for your RV if you have one. Your dock could probably use a little winter prep before those ice storms hit, too! Even if your area doesn't suffer the bitter winters of the Northern states, you shouldn't neglect winter preparations. According to BoatUS, most insurance claims for boat damage caused by freezing weather actually come from states where freezing temps are unusual. Unlike their northern neighbors, boaters in areas like Florida and California may not even think about freezing winter temperatures. Unfortunately, that unusual (and unexpected) cold snap could result in a cracked engine block or ruptured water lines. Don't risk significant damage to your boat from a freak cold snap, check out Defender's marine water system antifreeze.

The Basics of Winterizing Your Boat

Owner's manuals are your best source of information on winterizing your particular boat and its various systems. At a minimum, you'll want to protect your engine and water system (including the head). Expensive electronic equipment may be safer if stored in a temperature controlled, and secure, location for the offseason. Keeping the interior of your boat dry can prevent mold, mildew, and mustiness. Your furnishings will make it through winter in better condition if you prevent excess humidity from building up inside the cabin. Whatever you do to properly prepare for winter will likely save you money, stress, and extra work next spring. It can also mean getting back on the water sooner!

Defender's Winterization Checklist

These are 12 important winterization steps to take to protect your investment in your boat:

  1. Drain the engine to prevent a cracked engine block or manifolds.
  2. Flush the engine with non-toxic antifreeze.
  3. Stabilize the fuel to protect the carburetors and fuel injectors from clogs.
  4. Fog the engine cylinders to prevent corrosion inside the engine.
  5. Change the oil to get rid of any water that may be contaminating the old oil.
  6. Completely drain the fresh water system and add non-toxic propylene glycol antifreeze. Don't forget the water heater!
  7. Drain the head, flush it thoroughly, and add antifreeze (if recommended by the owner's manual).
  8. Make sure your batteries are fully charged.
  9. Turn off the refrigerator and freezer, clean them, and leave them open.
  10. Install a dehumidifier or use plenty of moisture absorber scattered throughout the boat.
  11. If you can't store your boat in climate-controlled storage, shrink-wrap it for the next best type of protection. Otherwise, use a boat cover or tarp to protect it from the harsh, wet winter weather.
  12. Don't forget to take any portable valuables home with you!

Our Collection of Winterization Products:

Why Winterize With Defender?

At Defender, we have been supplying boaters since 1938. We understand the investment that a boat represents and also how much enjoyment it provides for you and your family. That's why we want to do everything we can to help you keep your boat in great condition for all of the fun times to come! One of the best ways to protect it is by properly preparing it for freezing weather. Now is the time to order your boat winterization kit and any other supplies you will need to protect your boat. You want to be well prepared ahead of time for the winter that is inevitably coming. Be sure to check out our printable winterization checklist and contact us if you have any questions. We are always happy to help!

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