12 Important Steps For De-Winterizing Boats (For Beginners)

De-winterizing your boat is an important process for any boat owner. Almost as important as winterizing your boat!

If you’ve properly taken care of your boat before the winter, de-winterizing it should be pretty easy to do!

However, there are still many important steps and things to consider when de-winterizing your boat so that you will have a safe and enjoyable boating season.

Here are 12 Important Steps for De-Winterizing this Spring!

man charging boat battery by connecting the wires

1. Inspect the Battery

The battery life for a boat is roughly five years. It is important, then, to make sure that your battery held up well during the winter months.

Start by topping up the battery with fresh, distilled water if it needs it, and give it a good thorough charge.  Then, check the charge with a battery tester. If the battery still holds a strong charge, you’ll be in great shape!

If not, you may want to get it checked out or possibly even get a new battery altogether.  If you have time, look for a good sale, and get a good quality battery.

If the battery is in good shape, it’s still a good idea to scrub the battery clean of dirt or rust; anything really that can build up on it.  Next, clean the terminal post connections.  Make sure you remove the terminals and wires from the battery posts first!

Finally,  carefully reattach any wires or cables that were removed.  Then, coat those terminals with lithium grease to protect them further from corrosion.

All done!

2. Check for Worn Belts

How do you check for this? Good question!

A belt on your boat should not have a lot of “give,” meaning that if you press down on it or give it any pressure, it should hold tight.

Additionally, soot buildup on pulleys or belts is a bad thing. Any soot-worn belts need to be replaced immediately to prevent slippage, noise, or even breakage.

Any worn-down belts in the boat are going to need to be replaced. That’s that. There’s no reason to take a chance on a worn-out belt. Belts can be worn down without noticing it, and therefore they need a thorough check during de-winterization.

Don’t ignore these, and keep your eyes peeled for any issues that may arise!

3.  Inspect the Cooling System

When you store your boat for the winter or off-season, you would have either drained or put non-toxic antifreeze in the raw water side of an inboard engine cooling system.

If you did not check the raw water impeller’s condition, this should be done before you start the engine this season.  Any indication of wear means it should be replaced.  Checking the impeller of an outboard motor is also recommended.

The coolant side of the engine cooling system should also be checked.  If the coolant is dirty or rusty, it should be flushed out and replaced.  If the level is low, it should be topped up, now that you’re opening your boat back up for the warmer seasons!

Using equal parts, water and anti-freeze, fill your cooling system and then check all the hoses. You definitely want to keep an eye out for cracks, tears, wearing, or leakage.

If your coolant is dirty or rusty, change it out for a new coolant!

4. Test and Check on Your Electronics!

Every switch, knob, button, and meter needs to be tested and checked before you even think about sailing away on your boat after de-winterization.

You don’t want to be stuck out on the open ocean or in the middle of a lake and have something go wrong!

Flip every switch on the helm and in the cabins. Don’t skip a single one! The same electrical system connects everything, so keep an eye out for any circuit or area of the boat that may not be working.

Finally, now that the battery is up and running again make sure the automatic bilge pump is working. You don’t want to miss that very important step!

Make sure to check your user’s manual for any other electrical tips or sections that you need to be aware of or keep an eye on.

5. Inspect All Fuel Lines and Fluid Levels

Colder weather can be very difficult on your boat’s hoses, including fuel lines. You need to be sure that you do a thorough and detailed inspection of these fuel lines and other hoses.

Is your fuel filter clean and clear? If it is great! If not, get it replaced. As we mentioned earlier, you’ll want to make sure all fluids are filled to their appropriate level to prevent a loss of fuel or coolant when out on the water.

If your engine is not a two-cycle outboard, you should have replaced the engine oil when you winterized.  If not, it should be done before this season. In either case, always check the oil level before starting the engine the first time for the season.

Not only could low fluid levels cause problems, but the wear and tear on these systems will cost a lot of money in the future if not maintained properly!

6. Check on the Distributor and Spark Plugs

If your engine runs on gasoline, cleaning the distributor on your boat is very important.

When a distributor is neglected, it can corrode and cause poor engine performance and even stop it from running.   Instead, you’ll want to remove the distributor cap and make sure it is nice and clean.  If the contacts are corroded, replace the cap.

When you are done with that, make sure all spark plugs are in good condition and tight.

If it has not been done recently, a full tune-up with new spark plugs and even new wires is always a good idea.

7. Replace Your Zinc Anode(s)

If you replaced the boat’s zinc anodes when you winterized, you are good to go.

These are typically located on the underwater portion of an outboard motor, or on the propeller shaft of inboard boats; sometimes on the hull itself.  Zinc anodes are important because they prevent galvanic corrosion of metals on your boat and engine that occur in a marine environment, especially saltwater.

They are also called “sacrificial zincs” because they are designed to corrode before steel and other metals.  That means they are designed to dissolve and they need to be replaced regularly. 

Generally, if the zinc is has lost more than half of its original material, it should be replaced.

8. Watch Out for Animal Hibernation

Many people don’t consider that insects and arachnids may want to take shelter in their warm, covered boats.

Mice, in particular, have been known to gnaw into seating and make a warm nest there in the winter months. Don’t let this be you!

Make sure you NEVER have food left in the boat over the off-season to reduce rodent infestation. Also, check all nooks and crannies for any bugs or spiders that may have taken refuge in your boat.

If you find some unwanted critters, try using humane or non-toxic chemicals or traps that will remove them from your boat and send them on their way. Then be sure to…

9. Clean, Clean, Clean!

Especially if critters have taken to living in your boat in the off-season, you’ll want to clean the boat thoroughly before you let your friends, family, and pets onto your vessel.

One major but overlooked aspect of de-winterizing your boat is checking for mold.

Boats get wet. That’s standard. But that also means that mold and mildew can buildup on boats and vessels very easily if left unchecked. Make sure you are thoroughly cleaning any mold or mildewed areas of your boat.

Vacuum all storage spaces and seating, and while you’re at it, give the carpeting or wood on your boat a good scrub and maintenance treatment.

10. Check the Propeller(s)

While you’ve got the boat out of the water, let’s see how the propeller is doing, shall we?

Only in transit and when stored on-shore is your propeller out of the water. Now is a good time to check for dents, corrosion, or any loose or damaged parts.

You’ll also want to make sure that everything is in great shape and that nothing has been stuck or tangled in the propeller or the boat bottom that you missed when you winterized.

If you find that the propeller is damaged for some reason, you should remove it and have it repaired by a qualified shop, or even replace it, depending on the damage.

11. Polish and Wax

Many boat owners take a lot of pride in their boats, and this requires time and money.

They work very hard to keep them looking fantastic all year round. If you’re one of those, you may want to polish and wax your boat.

Supporting your boat in every way will keep you from having to repair or replace broken items before it should be necessary.  Boats are expensive, so even the littlest things can help keep them going for years! Save yourself some stress and money, and polish your boat!

Use a power washer on a light setting to get any dirt or mildew off your boat that may have built up over the off-season. Once done and dried, apply cleaner, buff, and apply products such as Shark Hide to keep it fresh and taken care of!

12. How’s The Trailer?

Just like your boat, the trailer is one of the most important things you’ll be using all summer.

You want to make sure your tires, attachments, and wires are all up to standard code.

Check the air pressure in your tires before using your trailer, and if one is flat or damaged, it’s time to replace it. You don’t want tire problems on the road.

It is legally required to have working turn signals on your boat’s trailer. Ensure all lights are working, and ask a family member or friend to keep an eye on them while you test your signals and brakes.

After those cold winter months, don’t be surprised if you have to replace a bulb.

Things to Consider Regarding the Engine

One of the most important things about your engine is keeping the engine oil clean and full.

With springtime finally here, you’ll want to make sure that your engine is getting a fresh start. That means checking your oil levels and changing them if necessary.  Whenever you change the oil, you need to change your oil filter, too.  Older engines may run better and last longer by using an oil additive.

Your engine is one of the most important parts of your boat and needs to be treated first. It is paramount that you consider your engine, all your fuel lines, and your fluid levels as soon as you start de-winterizing your vessel.

Other things to consider:

• Power Steering Fluid Levels
• Visible Cracks or Wearing in Fuel Lines
• How are your Coolant Levels?
• Is there Leaking below the Engine Area?

Specific Circumstances for Pontoon Boats

One of the greatest parts of a pontoon boat is the luxury that they can provide.

Most pontoons will come with many amenities, such as speaker sound systems, storage spaces, vinyl, canvas, and accessories.

When opening your pontoon boat back up for the warmer seasons, you’ll want to make sure that there aren’t any tears, leaks, breakage, or missing pieces of your boat.

Undercarriage and Leakage

The undercarriage of your pontoon boat is very important; most of all, the aluminum or steel floats beneath the boat are going to need your attention.

Check absolutely everything for any dents, cracks, or possible leaks. You’ll also want to make sure nothing was damaged during transit of your boat, and if there is damage, attend to it immediately.

Polishing Metal

Everyone knows that steel can rust, and other metals can corrode.

When you de-winterize your pontoon boat, make sure to keep an eye on your railings, metal, aluminum, and steel parts of your pontoon boat.

When left unpolished or untreated, a pontoon boat’s metal can begin to corrode, become damaged or weak. Since a pontoon boat’s buoyancy relies completely on the metal tubes they are made from, you want to make this part a priority.

Storage Spaces

You want to make sure you open everything up, including all your storage spaces, nooks, and crannies.

Storage spaces should be vacuumed out and re-stocked with all the supplies and emergency gear you may need. Any carpeting can be washed or cleaned as well.

Many animals or insects can get into your storage spaces. Don’t let yourself be surprised on a trip to the lake when you go to get your life jacket and are met with a family of rodents or spiders.

Make sure all these areas are clean!

Vinyl and Canvas

For example, many critters like to get into pontoon boats during the winter and will sometimes dig or burrow into seats or vinyl.

Similarly, the canvas can be torn by storms and weather events or get filled with nesting insects.

You also want to make sure that you prevent moisture and mold from forming on your canvas, which can be devastating for your health and the enjoyment of your pontoon boat.

If you do find that there are tears, rips, or damage to vinyl or canvas, you’ll want to either repair or replace those before you start your next season, and make sure to discover the cause of the damage. That way, you’ll be better prepared for your next winterization!

Final Touches

Keeping your boat up to date is a lot of work, so take a lot of pride in it and have fun!

Once you’ve got all the nitty-gritty work done, you can start adding all the fun stuff!

Water skis, fishing equipment, and boogie-boards are all going into those squeaky-clean storage spaces! Turn on those rewired speakers and start playing your favorite music. Stock up on sunscreen, as well as coolers with drinks and snacks!  Replenish or replace your first aid kit.

Add a fresh fire extinguisher for safety, and you’re ready to go!

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