How to winterize an outboard motor boat

Looking after your boat’s outboard motor is essential to keep it in top working condition, and that includes winterizing it.

How To Winterize An Outboard Motor

If you were to neglect the winterizing of your outboard motor, any residual water in the system could turn to ice and cause untold damage during a hard freeze.

But, if you were to properly How to winterize an outboard motor boat, this will prevent the formation of rust within the motor’s cylinders, thus enabling the motor to run as smoothly as ever.

In this article, we’re going to explain just how to winterize your outboard motor. And while there are quite a lot of steps involved, we’re pleased to report that it’s relatively easy and straightforward, and should not take you too long to do.

We’ll start by explaining the procedure for 2-stroke engines, followed by the procedure for 4-stroke engines. Here goes!

But before we begin, let’s make a note of all the tools and equipment you will need

Tools And Equipment Required

Here follows a list of all the tools and equipment required how to winterize an outboard motor boat:

  • A wrench set (included with your engine)
  • A small screwdriver
  • Some lubricating oil, such as marine grade grease or oil
  • A rag or paper towel
  • A hose clamp
  • A pair of gloves

When To Winterize Your Outboard Motor

You should winterize your outboard motor when you first put it away for the season.

This way, you can ensure that the motor has been thoroughly cleaned from dust and dirt, and also remove any excess moisture which may have accumulated inside the system.

The best time to do this is between October and December.

How to winterize an outboard motor boat

Winterizing a 2-stroke engine is relatively straightforward once you know what you’re doing.

So, let’s get started.

Remove The Carburetor Cover

The first thing you need to do is remove the carburetor cover. This can be done by simply lifting the cap off with one hand, then pulling the cover away from the motor with the other.

Once the cover has been removed, you’ll notice that there are two hoses running through the bottom of the cover. These hoses connect the carburetor to the air filter.

You’ll also see a hose coming from the side of the carburetor. This connects the carburetor to a fuel line which runs all the way down to the fuel tank.

As you can see, these hoses are pretty exposed to the elements, so make sure they’re protected well against the cold weather.

This means putting them inside some sort of container or wrap. You might want to consider using a small piece of plastic sheeting to protect them.

Now, once you’ve got everything covered, you can move on to removing the spark plugs.

Removing The Spark Plugs

To remove the spark plugs, first, loosen the retaining nut at the base of each plug. Then, pull the plug straight out.

Now, before replacing the plugs, make sure to clean them thoroughly. This will ensure that no dirt remains behind, which would otherwise interfere with the flow of electricity.

Next, replace the plugs. Make sure to tighten the nuts back down firmly.

Finally, put the cover back on the carburetor. And you’re done.

YouTube Video

But we get how it can be tricky to do if you’ve never done it before and don’t know which part is which, which is why we’ve also found this YouTube video to help you. Check out this video.

How To Winterize A 4-Stroke Engine Outboard Motor

Winterizing a 4-stroke engine is a bit more complicated than doing so with a 2-stroke engine.

The key difference is that you have to remove the oil pan.

The reason why you have to do this is that the oil pan acts as a heat sink. It keeps the oil warm enough to remain liquid throughout the winter months.

And since the oil pan is connected directly to the block, you have to disconnect it before you can remove the oil pan. So, here’s how to do it:

Start by loosening the bolt holding the oil pan in place. Once the bolt has been loosened, lift the oil pan up and slide it towards the rear of the boat.

Then, use a socket wrench to unscrew the bolts connecting the oil pan to the block.

Once the oil pan is disconnected, you can now remove it.

Now, you’ll need to remove the oil pump.

To do this, first loosen the retaining screw at the top of the oil pump. Then, carefully pull the pump out of its housing.

Now, before you replace the pump, make sure to clean it thoroughly. Dirt and debris can cause problems for your engine.

After cleaning the pump, reassemble it into its original position.

At this point, you should be able to remove the oil pan again.

Before replacing the oil pan, though, you’ll need to check the condition of the gaskets. If any of the gaskets are damaged or worn, you’ll need to replace them before reinstalling the oil pan.

If you find any damage or wear to the gaskets, you’ll need to get new ones.

YouTube Video

But we get how it can be tricky to do if you’ve never done it before and don’t know which part is which, which is why we’ve also found this YouTube video to help you. Check out this video.

Wrap Up

Ok, so that just about covers it. You now know when and how to winterize an outboard motor boat, whether it’s a 2-stroke or a 4-stroke, and you’ve got a run down of all the tools and equipment you need.

We think you’ll find the YouTube videos provided particularly helpful, and we recommend that you watch the relevant one in full before you get started.

As we said in our introduction, it’s relatively simple and straightforward, and is something you can easily do yourself once you know how to winterize an outboard motor boat.

And before you know it, winter will be over, and you can go back out on the boat again!

Jacob Beasley
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