How to Winterize an Inboard Boat Motor?

Last Updated on October 1, 2022

If you own an inboard boat, it’s important to winterize the motor to prevent damage from freezing temperatures. Here are some tips on how to winterize an inboard boat motor: 1. Remove the spark plugs and spray a fogging oil into the cylinders.

This will lubricate the engine and prevent corrosion. 2. Change the oil and filter. Be sure to dispose of the used oil properly.

3. Drain the cooling system and add antifreeze. Don’t forget to flush out the bilge area as well! 4. Cover or store your boat in a dry, protected place to keep it out of the elements during winter months.

5. Check your batteries and give them a full charge before storing for winter. By following these simple steps, you can help ensure that your inboard boat motor will be ready to go when spring arrives!

  • Assuming you have a water-cooled inboard boat motor, the following steps should be taken to winterize it: 1
  • Remove the drain plug from the hull and allow the water to drain out
  • Flush the engine with fresh water using a hose and make sure all of the salt is removed
  • Add antifreeze to the cooling system according to manufacturer’s instructions – typically, this means adding it to the raw water side of the system
  • Run the engine until it reaches operating temperature, then turn it off and allow it to cool completely
  • Disconnect the battery so there is no chance of electrical damage over the winter months

How to Winterize an I/O Boat using Inboard/Outboard Kit, Step by Step Guide

How to De-Winterize a Boat Engine

Assuming you have a boat with an inboard motor, here are the steps to take for de-winterizing your engine. Note that this process will be different if you have an outboard motor. 1) Remove the spark plugs and squirt a teaspoon of oil into each cylinder.

Replace the plugs and hand-crank the engine over a few times to distribute the oil. 2) Fill up the gas tank and add a fuel stabilizer to help keep the gas fresh over the winter months. 3) Change the oil and filter according to your manufacturer’s recommendations.

This is typically done every 50 hours of use or once per season, whichever comes first. 4) Inspect all belts and hoses for cracks or wear and replace as necessary. 5) Check coolant levels and add more if needed.

Make sure to use a 50/50 mix of water and antifreeze. 6) Flush out the old antifreeze from your cooling system using fresh water mixed with a non-toxic RV holding tank cleaner (available at most marine supply stores). Run the engine for a few minutes to circulate the cleaner before draining it again.

Finally, refill with new antifreeze mixture as described in step 5. 7) Lubricate all moving parts on your engine according to your manufacturer’s instructions – this typically includes items such as control cables, throttle linkages, etc. 8) Check your battery voltage and charge as necessary – batteries typically lose about 30% of their power over winter months even when not in use, so they may need to be replaced entirely come springtime if they’re not properly maintained during winter storage.

. If you have any doubts, it’s always bestto err onthe sideof cautionand geta newbatterybefore takingyourboatoutforthefirsttime nextseason!

How to Winterize a Boat

Assuming you have a sailboat, winterizing it is actually not that difficult or time consuming. The main goal is to make sure as much water as possible is removed from the boat so that it doesn’t freeze and cause damage. Here are the steps you need to take:

1. Remove all sails and canvas covers. These should be stored indoors for the winter. 2. Take out all removable cushions and store them in a dry, protected place.

3. Drain all fresh water from the boat, including the tanks and lines. You can use a siphon to speed up this process. 4. Disconnect the battery and bring it indoors for storage.

5a). If your boat has an inboard engine, add fuel stabilizer to the gas tank and run the engine for a few minutes to circulate it through before shutting down for winter..

5b). If you have an outboard motor, flush it with fresh water after every use and then fogging oil into the cylinders following manufacturer’s directions 6. Thoroughly clean the entire boat inside and out so mildew doesn’t have a chance to form over winter.

How to Winterize a Sterndrive Boat

If you have a sterndrive boat, you’ll want to take some extra steps to winterize it before putting it into storage for the season. Here’s what you need to do: 1. Drain the oil and replace it with fresh oil.

This will help protect your engine during the winter months. 2. Remove the spark plugs and spray a little bit of WD-40 into each cylinder. This will help prevent rust and corrosion while the boat is in storage.

3. Fill up the gas tank and add a fuel stabilizer to keep the gas from going bad over the winter. 4. Take out any batteries that are in the boat and store them in a warm, dry place. Batteries can freeze and become damaged if they’re left in cold conditions for too long.

Boat Winterization Checklist

It’s that time of year again. Time to winterize your boat. Whether you’re putting your boat away for the season or just preparing for a cold snap, follow this checklist to make sure your boat is properly winterized.

1. Clean Your Boat Give your boat a good cleaning inside and out before winterizing it. This will remove any dirt, grime, or salt that could corrode your boat over the winter months.

2. Change The Oil And Filter Fresh oil and a new filter will help protect your engine during the colder months. Be sure to consult your owner’s manual for the correct type of oil and filter for your engine.

3. Fill The Fuel Tank And Add Stabilizer Adding fuel stabilizer to your tank will help keep the fuel fresh all winter long. Be sure to fill the tank all the way up to help prevent condensation from forming inside the tank which can lead to corrosion. 4. Drain The Water System All water must be drained from the water system including: freshwater tanks, hot water heater, bilge, and engines (including coolant).

Once everything is drained, add RV antifreeze to all drains, traps, and toilets according to manufacturer’s directions (typically 1/2 cup per gallon of holding tank capacity). If you have a pressure-type water system , you’ll also need to add antifreeze directly into the pump by-pass valve following manufacturer’s directions . 5 .

Fog The Engine Fogging the engine helps prevent corrosion during storage by coating all internal surfaces with oil . To fog an engine , simply run it at idle until thick white smoke appears from the exhaust . You may need to add fogging oil through the carburetor if your engine does not have an automatic oiling system .

Consult your owner’s manual or engine manufacturer for specific instructions on how much fogging oil to use as well as whether or not you need special tools such as an adapter kit in order to do this correctly without damaging your engine . 6 . Remove The Battery And Store It In A Warm Place Batteries discharge more quickly in cold weather so it’s best to remove them from the boat and store them indoors where it’s warm . If you don’t have space indoors , make sure they are stored in a battery box or some other type of protected container outdoors where they won’t get too cold .

How to Winterize an Inboard Boat Motor?


How Do You Winterize an Inboard Boat Engine?

Assuming you have a freshwater cooling system: 1. Start by draining the engine block. Remove the drain plug from the front of the engine block and allow all the water to drained out.

Some engines also have a rear drain plug that should be removed as well. 2. Once all the water is out of the engine, remove the raw water pump impeller and inspect it for wear or damage. If necessary, replace the impeller with a new one.

3. Next, disconnect the hoses from the raw water side of the heat exchanger and bypass valves (if equipped). Be sure to label all hoses so you can easily reconnect them come springtime. 4a.

If your boat is stored indoors or in a heated space, you can simply leave your antifreeze in the engine and add more as needed throughout winter. Just be sure to check levels periodically and top off as needed. 4b.

If your boat is stored outside or in an unheated space, you’ll need to completely flush out your cooling system and refill it with RV-type (non-toxic) propylene glycol antifreeze mixed with distilled water per manufacturer’s recommendation – typically 50/50 mix for boats without aluminum components and 60/40 for boats with aluminum components such as manifolds or risers.. To flush out your cooling system, run fresh water through all circulating pumps until it comes out clear at each hose connection point – typically raw water intake strainers, exhaust outlets (including wet exhaust mufflers if so equipped), and any seacocks or thru-hull fittings that are below the static waterline.

. 5) Once everything is flushed out, reattach all hoses making sure they are snug but not too tight..

6) Fill up your cooling system with a 50/50 mixture of RV-type propylene glycol antifreeze mixed with distilled 7) Run engine long enough to circulate antifreeze throughout entire system – being careful not to overheat engine since there’s no longer any water in system to help dissipate heat.. 8) Shut down engine and allow to cool completely.. 9) Inspect all belts for cracks or excessive wear and replace if necessary.. 10) Change oil & filter according to manufacturer’s recommendations..

Do You Need to Winterize an Inboard Outboard Motor?

Assuming you are talking about a boat with an inboard outboard motor, the answer is yes, you need to winterize it. Here’s why: Water expands when it freezes, and that can cause all sorts of problems for your boat’s engine.

The water in the cooling system can freeze and crack the engine block or damage other vital parts. So it’s important to make sure all the water is drained from the engine before winter sets in. Here are some tips for winterizing an inboard outboard motor:

1. Change the oil and filter – This will help remove any water or contaminants that might be in the oil, which could cause damage over the winter months. 2. Drain the fuel tank – Water can condense inside a fuel tank and cause corrosion or clog up the fuel lines. Draining the tank will also help prevent any issues with stale gas.

3. Remove spark plugs – This will help protect them from corrosion over winter. Be sure to label them so you know where they go back in! 4. Fogging the engine – Fogging agents help protect engines from corrosion by forming a thin film on metal surfaces.

How Do I Add Antifreeze to My Inboard Motor?

There are a few things to keep in mind when adding antifreeze to your inboard motor. First, make sure the engine is cool before starting. You don’t want to add hot water to the system.

Second, use a funnel and pour the antifreeze into the radiator filler neck. Be careful not to overfill; you should leave about an inch of space at the top of the radiator so that it doesn’t overflow when the engine gets hot. Finally, start the engine and let it run for a few minutes so that the antifreeze can circulate through the system.

Can I Winterize My Boat Myself?

As the weather starts to cool down and winter approaches, boaters across the country begin to think about winterizing their vessels. While some choose to have a professional do it, others decide to take on the task themselves. But is this really something that the average person can do?

The answer is yes, you can winterize your boat yourself with relative ease. The most important thing is to make sure that you thoroughly clean and dry out your boat before putting it away for the season. Once that’s done, you’ll need to add antifreeze to any water systems on board (such as toilets, sinks and showers) and also change the oil in your engine.

Of course, there are other steps involved in properly winterizing a boat – but these are the basics. So if you’re feeling confident and want to save yourself some money, go ahead and give it a try! Just be sure to do your research first and always err on the side of caution.


Assuming you have a basic understanding of how your inboard boat motor works, winterizing it for storage is a pretty simple process. You’ll need to perform a few key maintenance tasks to make sure your engine is protected from the elements and ready to go when spring rolls around. First, give your engine a thorough cleaning both inside and out.

This will remove any dirt or debris that could cause corrosion or other damage over the winter months. Next, change the oil and filter according to your manufacturer’s recommendations. This will help remove any contaminants that could harm your engine while it’s not in use.

Once those two important steps are taken care of, you’ll need to add some fresh fuel to your tank and then treat it with a stabilizer. This will prevent the fuel from breaking down and causing damage to your engine. Finally, run the engine for a few minutes so the stabilizer can circulate through all of the system’s components.

With those few simple steps, your inboard boat motor will be properly winterized and ready for storage until next season!