How To Dewinterize A Boat: (13 Step Checklist) To Summerize Your Boat

Things You Should Do To Summerize Your Boat For The Season

When I first got my boat, it was in the fall and that lead to me immediately thinking about winterizing the boat. 

Since I didn’t know the exact maintenance history at this time so I decided to just bring it in and have them do a once over and winterize it after everything checks out.

But after the boat was winterized and tucked in the garage snug as a bug in a rug, I started thinking what about summarizing?

That’s when I started to research…

I found out that antifreeze is non-toxic and safe for the environment…

Oh so “they” claim.

 So I’m assuming that some individuals drop their boat on the lake first thing in the spring and fire it up drawing in the lake water and shooting out a non-fish harming concoction that has been sitting in your engine all winter long.

This is something that I wouldn’t even recommend doing…I recommend putting on the muffs for the outdrive and run your boat in the driveway first and therefore have the opportunity to make sure everything is running properly.

You don’t want to get to the boat launch and launch your boat with dead batteries or some silly oversight that will ruin your first boat launch of the season.

But this is just one of the ten steps I put together for you to ensure you have your boat all set before starting your boating season

Let’s get to it….

13 Steps To Ensure Your Boat Is Ready For The Season

1. Engine Oil and Fluid Levels

One of the first things you should do is check the oil and fluid levels in your engine. I personally change my oil in the fall as part of the winterization process. 

But if you do not do it this way, this is the time for you to put fresh oil and new oil filter on your engine. Make sure your levels are where they are needed and your good to go.

2. Sterndrive Oil

If you have an inboard/outboard, you may have changed the lower gear oil. If you did not replace it before storage, you should do this now. Also, impact the oil for any sign of water that may be getting in. If you see milky watery oil, you may have a crack or leak somewhere that you want to get resolved before taking it out on the water.

3. Refill The Cooling System

Typically your cooling system should be drained for winter storage. But, if you have not done this, it is time to get it drained and refilled. If your boat is water-cooled like mine, the main focus is making sure your impeller is good for the season. You need to make sure your water pump is doing its job before launching your boat.

4. Check Your Batteries

Make sure your batteries are in proper working order. Grab a battery tester and make sure your batteries are putting out the correct amps and volts. Also, ensure they are holding a charge and if not go ahead and replace them.

5. Clean The Distributor

Distributor caps can get corroded over long winter months and would advise you to take it off and inspect for any damage.

6. Examine Your Fuel System

The main thing here is to make sure your fuel lines are not cracked or brittle that can happen during the cold winter months

If they are cracking or showing signs of wear, they will need to be replaced before launching your boat. You do NOT want any fuel leaks in your bilge that can cause any explosions! 

7. Inspect Your Trailer

Look at your tires and make sure they are not cracked or leaking air. Also, inspect your lights making sure they are all working as needed.

8. Check For Worn Belts

Inspect your belts for cracks or other major stretching that may have occurred that will require them to be replaced.

9. Test the Electronics

  • Bilge pump & float switch
  • Bilge blower
  • Horn
  • Trim 
  • Fishfinder
  • Any other electronics you have on your boat

10. Make sure your safety gear is in order

  • Throwable flotation device
  • Fire extinguisher (check expiration dates)
  •  Horn or whistle
  • Any paperwork you may need

11. Inspect Water Pump Impeller

If your boat is water cooled, it is extremely important to make sure your impeller that provides the water to cool the engine is in good condition. 

Make sure the fins on the impeller are not cracked or broken off. Impellers are usually replaced every 3 years to ensure you don’t have an overheating problem with your engine that could be potentially catastrophic 

12. Clean And Wax

Now it the time to get your boat all nice and shiny again. After being stored they are usually not the cleanest. To get your boat looking good for the new boating season, clean and get any oxidation off the hull and apply a fresh layer of wax.

13. Inspect your covers

Look at your covers and make sure you have any major rips or snaps that may be damaged. Cover can take a beating in the hot summer sun, so they may have to be replaced over time.

Commonly Asked Questions

  • Do I need to do anything before I take her on the water?- Yes follow the checklist above to make sure your good for the season
  • Will my engine just run full of antifreeze? Yes, you will run your engine in the water or using clamshells and a hose to flush all the coolant out and draw in fresh water.
  • Did I store my batteries correctly over the winter? I take mine out and place them inside the house but you can leave them in the cold as long as they are disconnected and fully charged.


Now that your boat is inspected, washed and wax, you’re ready for a great time on the water. It is always good to inspect your boat between outings in ensuring you won’t have any problems on the water. We hope this article is helpful and happy boating...

Project “Ready For Summer” Boating

Check out our article on: How Much Does it Cost to Winterize a Boat: (DIY and Serviced)

Photo of author

Project Boating Editorial Staff

My name is Brad Visser the chief editor and owner of We have an amazing team of writers that contribute to our website. This team is passionate about boating and have years of experience not only in boats, but in writing helpful, informative articles to answer questions you may have.

Keep in mind that we may receive commissions when you click our links and make purchases. However, this does not impact our reviews and comparisons. We try our best to keep things fair and balanced, in order to help you make the best choice for you.

As an Amazon Associate, I earn from qualifying purchases.