Winterizing Outboard Motors

Easy things you can do to be ready for spring fishing in Ontario.

With the investment anglers have in their boats and motors, it’s surprising to see the number of people who have problems on the season's first trip, especially when a little maintenance in the fall would all but eliminate them. Sitting under a pile of snow all winter can really take a toll on an outboard motor and, regardless of how well your engine worked last season, without a little care before winter, you’re setting yourself up for trouble next year.

Here are a few easy things you can do to help keep your motor in good shape through the winter so it’s ready to go next spring.

changing boat oil

Change the Lower Unit Oil

The first thing to do is change the oil in the lower unit. This ensures that 

  1. There is no water in the gear case that could freeze and cause a crack
  2. Can alert you to any potentially serious internal problems.
tilting a boat engine

Change the Gear Oil

To change the gear oil, start by tilting the engine into the “down” position so that it is as vertical as possible. Place a catch-tray under the engine and locate the two or three screws on one side of the lower unit housing. If you have a large outboard, you may need to remove the propeller to access the lowest of these.

removing screws on the gearcase of a boat

Remove the bottom screw first, then the top one(s) and let all the oil drain out of the gear case. The lower plug will have a small magnet on it that is there to attract any metal filings that may have worn off the gears. A few filings are normal, but if you notice an unusually high amount of them it could be a sign of pending engine damage—have the engine checked by a professional. While you have the plugs out, replace the small gaskets on all of them and clean off any debris.

draining boat oil

While the oil is draining, take a look at its colour. The old oil should look like old oil; if it looks whitish and creamy, it’s a sign that water has been getting into the engine somehow. Water in the gearcase is a guaranteed recipe for disaster so, if the old oil doesn’t look right, take the engine to a dealer and have it checked.

re-filling the boat gearcase

Once the old oil has drained, re-fill the gearcase with the manufacturer’s recommended oil. Always fill the gearcase from the bottom hole and keep pumping it in until oil begins to ooze from the top hole.

re-installing the upper plug of the gearcase

When you see oil coming out of the top hole, re-install the upper plug(s) to create a vacuum. Then remove your oil pump or tube of lubricant and quickly re-install the lower plug.

fill the gas tank of a boat

Fill the Gas Tank and Add Fuel Stabilizer

Next, fill the gas tank(s) and add fuel stabilizer if the boat won’t be used for several months. This eliminates the possibility of condensation forming inside the gas tank, which could contaminate the fuel and possibly foul the engine. The stabilizer will also prevent the fuel from breaking down and becoming gummy, which can happen to untreated fuel in as little as three months.

Don't Forget These Motor Winterizing Tasks

  • It’s a good idea to change the spark plugs every season too, especially if you use your rig a lot, and by doing it in the fall, you’ll ensure an easy start-up in the spring.
  • Finally, take a grease gun and give a squirt to any of the grease fittings on the engine. Visually check the engine, especially around the propeller, and remove any fishing line, vegetation, etc.
  • Give the motor a quick wash to keep it looking good, cover it up, and you’ll be all set to go when next spring rolls around.
About Bob Izumi

Bob Izumi is a Canadian professional angler, and the host of Bob Izumi's Real Fishing Show. He is most known for his success in bass fishing, and was awarded angler of the year in 2004.

Recommended Articles

Muskie Fly Girls

Lac Seul turned a trail of broken hearts into a circle of fishing friends.

Top Three Ontario Musky Waters

Where to catch the fish of 10,000 casts.

Outfitter Tough, Guide Tough

Backcountry Brook Trout Fishing at Air-Dale

Top 5 Things to Bring on a DIY Fishing Trip

Your outfitter will drop you off with all your essentials.

Creating an Angler

Family Fishing in Northern Ontario

Sharpshooting Crappies

Check out this fishing technique for landing a few fall black crappie

Camp Conewango

Lake Talon Smallmouth Bass Fishing

Fish TV On the French River

The French River/Georgian Bay area is a favourite hotspot for the Fish TV team.

Trophy Fishing at Seine River Lodge

The Seine River is very large, and it seems like a chain of lakes

Tag Team Walleye

Experience the fishing at White Moose Wilderness Outpost.

5 Tips for your Fly-in DIY Adventure

Imagine fishing on a secluded pristine remote lake.

Weighting for Panfish

Ice fishing for Ontario Panfish

Birch Dale Lodge

Discover why muskie fishing in Ontario's Sunset Country is world-class!

Fly Fishing at Anderson's Lodge

A smallmouth bass fly fishing adventure to this famous lodge on Lac Seul.

Lac Seul

One of the Most Productive Walleye Fisheries on Earth

Chasin’ Fall Critters

Casting or trolling, what's best for musky and pike?

Supernatural Fishing

With plenty of ice late winter is the perfect setting to ice fish for northern pike.

Sunset Cove Resort

Lake of the Woods and fishing and of course...sunsets.

Going the Extra Mile

How far will you go to find the fish?

Run and Gun Your Way Through Canada

Experience the incredible thrill of musky fishing across Ontario, Canada.