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How to Winterize Outboard Motor & Store Battery in Cold Weather: Comprehensive Guide

How to Winterize Outboard Motor & Store Battery in Cold Weather: Comprehensive Guide

Written by Flora on . Posted in Electric Boating Blog.

Outboard motor winterization can be a big hassle if you are a new boater, including changing the oil regularly, fogging the engine, changing the gear lube, and many other hassles. Even if you have many years of experience in winterizing the outboard motor, the cost can be a burden considering the lifelong service years. If you are looking for an easy way to winterize outboard motor, read this post for some fresh ideas (together with even more benefits than saving the service labor!)

Do You Have to Winterize an Outboard Motor

A simple answer is YES.

Before we dive into details, it is important to understand that outboard motor winterization is necessary for all types of engines although some outboard motors offer easier maintenance than others, saving you a lot of time and money in the long run.

If you don’t want to see the corrosion, buildup, old fuel, and rust on the outboard motor when you use it next time, you should take the outboard motor winterization seriously. The thing is that if you just leave the outboard as it is for the winter, the acidic and corrosive wastes inside, remaining fuels, and the mold and mildew can be harmful over time.

The outboard motor winterization is especially important for the areas where temperature can drop below freezing. The water will freeze and expand, which can damage the internal parts.

Note: Most of the tips are applicable for motors you are planning on not using for a long time, not just for the wintertime.

How to Winterize Outboard Motor: An Easy Shortcut

So, if you are dealing with combustion motor, the outboard motor winterization checklist can go through pages on the user manual, from the draining and flushing to the more technically demanding tasks including lubricating moving parts, greasing prop shaft, and diagnostic computer check for hours/codes which is easier to be handled by the service person.

You may check the complete steps to winterize outboard motor here to learn the details.

Tired of winterizing the outboard motor and repeating the steps every year?

The electric outboard motor can minimize your effort in the outboard motor winterization. Let’s see what users say about their winterization experience with electric motors:

“2021 boating season is underway here in Virginia! My Navy 6.0 hadn't been touched all winter but didn't show any ill effects. My friends with gas outboards always complain about the hassles of winterizing their motors; not having to deal with that is one of the under-appreciated aspects of electric outboards.”

-Matt Langford, ePrpoulsion outboard owner

With the electric powering nature, there is no need to deal with the oil, fuel, water, and related parts during the winterization. Basically, you just need to make sure it can survive for the long-term disuse with some easy operations including the following:

  • Have the outboard cleaned and checked (especially the more vulnerable parts including the connectors) prior to storage to prevent corrosion.
  • Take adequate damping-absorber for protection before transport and storage.
  • Ensure the propeller receives no pressure if it is installed on the propeller shaft.
  • Store the outboard in a dry, well-ventilated place without direct sun exposure.

Besides that, remember to take care of the batteries in the cold weather to make sure everything is covered during the outboard motor winterization process. Other than that, no extra effort is needed for winterizing the outboard motor.

Extra notes and tips:

  • If you are using a remote controller together with the outboard, don’t forget to charge the control system every 6 months to avoid over-discharge.
  • It’s also recommended to pack the outboard with the accompanying package during the outboard motor winterization period.
Outboard Motor Winterization

Proper Battery Storage in Cold Weather is Crucial for Outboard Motor Winterization

If you are using an electric motor, you already got the fast pass on the outboard motor winterization procedure. However, don’t forget to properly store the battery for the cold weather.

So what management is needed for the winter? What is the best way of storing the battery over winter? On charge, full charge, half charge?

No worries. The procedure is pretty easy compared with the outboard motor winterization steps required for combustion outboard. Here we take the ePropulsion electric outboard motor (lithium-ion batteries are used) as an example:

  • Store the battery in 15°C ~ 25°C (59°F ~ 77°F) ambient temperature.
  • Before winterizing your outboard motor, ensure the battery charge level is 60% around.
  • During the long-term storage, activate the battery every 3 months by charging to keep the battery charge level at 60% around the maximum. This activation is very important which can help to keep the battery in good condition.
  • After the outboard motor winterization, fully charge the battery before it is ready for use.

Also, don’t forget to clean the connectors to prevent possible corrosion during winterization.

Note: Storing the battery at high battery capacity will damage the battery by reducing its lifespan, and even cause potential security issues. For lithium-ion batteries, it is suggested to keep them at a reasonable level between the cut-off voltage allows and 60% maximum during storage. So it’s recommended to discharge the battery to around 60% prior to storage if it starts at a higher battery level.

Your Thoughts

Outboard motor winterization should be taken into consideration when deciding the electric or outboard motor for your boat because it can be a long-term effect for your boating journey.

Let us know your thoughts and which solution you prefer for the yearly outboard motor winterization steps in the comment area or if you have any problem during wintering your outboard motor, I will get back to you as soon as possible.