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Outboard Motor Winterization Tips

With temperatures dropping and the signs of winter well on the way, we boat owners are faced with the sad fact that it is time to put the boats to bed. Seeing them blocked up and covered over beneath a deep layer of snow is one of the more depressing sights of a boat owner. Before we can truly tuck the boat in for its hibernation, there are several things we have to take care of in order to ensure it makes it through the winter without any difficulties. One of those things is winterizing the motor properly, specifically we will look at outboard motor winterizing before storing them.

Outboard engines in rest

 

The Winterization Process

 

To properly winterize our outboard motors there is a process that must be followed. Doing things improperly can lead to major problems when we go to start up next years boating season.

 

Fuel Stabilization

 

At the end of the season don’t be afraid to leave some gas in the tank. It’s recommended to leave the gas tank around 75% to 90% full to prevent the build up of moisture on the inside. Avoid filling it up 100% as temperature changes can cause the fuel to expand, which could possible warp the tank and or spill out the overflow vents.

 

Once you’ve left the fuel at the level of your choice you need to add stabilizer to it. Leaving gas to sit for months allows it to break down, which will leave you with “sour gas”. Having to deal with that is going to be a wet blanket on the start of your boating season. Once stabilizer is added, run your engine for 15 or 20 minutes to circulate it through the motor and fuel lines.

 

Before you do this, adding a gas line antifreeze is always a good idea as well. This will remove excess water and moisture from the gas and lines, which will prevent it from freezing and rupturing the gas lines.

 

You can of course leave the tank completely empty if you so wish, that is completely fine a well. Just make a decision between partially filled and empty. If you do leave the tank empty then you should run the fuel right out of the motor, simply start it and let it run until it stops.

 

Drain The Water

 

Boat motors are water cooled by drawing water up into itself and circulating it throughout the engine block. Naturally when water temperature drops below 0° it freezes, if there is any water left in the motor this can result in the engine block cracking. Just like that your motor is done. After draining the water you could just leave it at that, but any remaining water is a risk, so that’s why we recommend taking things further by running antifreeze through as well.

 

Adding Antifreeze

 

As the name implies, antifreeze will prevent ice build up, avoiding cracking of engine blocks and fuel lines. There are several types available depending on just how hard your winters are, but we recommend simply using the highest concentration just to be on the safe side. Ensuring proper and complete circulation is a key component, and the best way to do it is simply running the engine, you will be doing this anyways for the fuel stabilizer.

 

Conclusion

 

We consider what’s been discussed here to be the bare essentials for winterizing your outboard motor. For complete steps, ask your marina, a trusted advisor, or simply have them do it for you if you aren’t comfortable doing it yourself. Most marinas offer storage and winterization services for their clients.

 

Should you choose to store your motor elsewhere for the season, we can offer a variety of units. Some of them are heated units, which provides you with an easier way to keep your motor safe during the winter, although it is highly recommended to do things properly just to be on the safe side.

 

Here’s hoping next boating season comes quickly!