How to Winterize a Boat with Inboard Motor [8 Steps]
Most people don't boat in winter due to the dangers of cold water temperatures, icy lakes and streams, and other factors. Boats often sit for months without use, which can damage the motor if it isn't adequately prepared.
If you're unsure how to winterize a boat with inboard motor, we're here to help. Fortunately, there's a process you can follow that will make winterizing easier. Then, you can feel confident that you're protecting your boat during the colder months.
Here's what to know to keep your boat safe all winter long so it will be ready when warmer weather returns. Even if you've already winterized for this year, read through these tips to make sure you've done everything your inboard motor needs!
Why Winterizing Is Important
Setting up a boat for winter is valuable because it protects the engine and other components from freezing or corroding. This can prevent costly spring repairs and ensure your boat is ready for the next season.
Along with keeping your vessel insured, properly winterizing and storing your boat is one of the best ways to protect it. You don't want to plan to head out on the lake, river, or ocean and find that your boat's engine has sustained damage over the winter months.
Preparing Your Tools and Supplies
Before you start the winterization process on an inboard motor, you want to get everything you'll need for the process.
Some of the tools and supplies you'll need include:
- Antifreeze Designed for Marine Engines
- Fogging Oil
- Fuel Stabilizer
- Pliers, Wrenches, and Basic Tools
- Funnels, Buckets, and a Garden Hose
- Cleaning Materials
- Marine-Grade Lubricant
Being prepared can make the process less stressful, especially if you're doing this for the first time.
How to Winterize a Boat With Inboard Motor: 8 Steps
Here are the specific steps you'll follow when you need to know how to winterize a boat with inboard motor.
Step 1: Drain Water from the Cooling System
To prevent the cooling system from freezing and cracking the engine block, you need to remove all the water.
Locate the drain plugs and open them to drain the water. If there are stubborn water pockets, you can use a vacuum pump or compressed air to clear them.
Step 2: Flush the Engine
Next, attach a garden hose to the boat's flushing port. Run fresh water through the system to help remove debris.
If you use your boat in saltwater, salt will also be cleared from the boat's cooling system.
Step 3: Add Antifreeze
Once the engine has been drained and flushed, it's time to add antifreeze. You can mix your own or use pre-diluted marine antifreeze.
Pour this into the engine until it circulates through the cooling system. The size of your boat's engine and other factors will affect how much antifreeze it takes.
Step 4: Treat the Fuel System
Along with the cooling system, you need to protect the fuel system. You can do that by adding a fuel stabilizer to the tank.
Don't forget to run the engine briefly to circulate the stabilizer throughout the system.
Step 5: Fog the Engine
Fogging oil coats the cylinders, helping prevent rust while storing your boat. Remove the spark plugs and spray fogging oil directly into the cylinder heads to fog the engine properly, then put the spark plugs back.
Step 6: Change the Oil and Filter
When you change the oil, you remove contaminants and help reduce wear on the engine's internal parts. You should also change the filter every time you change the oil for maximum benefit.
Step 7: Lubricate Key Components
Lubricating key components of your boat will keep them from seizing up during the winter. Be sure to grease the throttle, shift cables, and steering mechanisms.
While you're doing this, take time to inspect and lubricate any other moving parts. You'll be glad you did when spring comes around.
Step 8: Check Belts and Hoses
Inspecting belts and hoses can help spot cracks, wear, or leaks. If you spot worn-out components, make a note of them and replace them before spring boating season arrives.
Additional Winterization Tips for Any Boat
When setting up a boat for winter, there are some additional tips to consider.
These include:
- Disconnect the battery and store it in a cool, dry place.
- Keep the battery strong during the offseason by charging it periodically.
- Clean the engine and bilge area.
- Choose a specialized engine cover or other breathable fabric to protect the boat's engine.
- Store the boat in a dry, secure location, or choose a shrink-wrap cover.
Following these extra tips will give your boat the best chance at being ready for spring when you want to take it out on the water again.
3 Common Mistakes to Avoid
Many people make some serious — but common — mistakes when considering how to winterize a boat with inboard motor.
Try to avoid the following three mistakes when setting up a boat for winter:
- Using automotive antifreeze instead of marine-grade.
- Skipping the fuel stabilizer, which leads to varnish build-up.
- Forgetting to fog the engine, causing the cylinders to rust.
If you're unsure of any of the steps or equipment to use when winterizing a boat, a professional can help.
Learn About Boater Safety During the Off-season
Just because your boat is out of the water doesn't mean you can't keep your mind on boating safely during the upcoming season! Along with understanding how to winterize your boat, taking a boater education course to learn about safety on the water is an excellent thing to do during the off-season.
BOATERexam makes it easy to stay informed about safe boating practices and regulations in the U.S. and Canada. Our online course helps you protect yourself and others safe on the water when it's time to launch again in the spring.
So, after winterizing your boat, choose the BOATERexam course that applies to your state and learn how to stay safe when operating a boat! In Canada, choose our course for Canadians — approved by Transport Canada.
After completing the course and passing the exam, you'll get your boater education card to carry with you during your next boating adventures.
