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

Top 5 Flies for Brook Trout

Favourite fly patterns from The New Fly Fisher

Cast Back for Giant Muskies

Some of the biggest muskies I’ve caught over the years have come on cast-back baits

3 Great Baits For Northern Bass

What should be In your tackle box on your next fishing trip.

Birchland Cottages: Modern comfort with classic Northern Ontario charm

This Clear Lake gem is a great for kids, and the fishing action is non-stop.

Wild Brook Trout

Remote Outpost Fishing on Pinei Lake

Basin-Shape Walleye

Learn this proven technique to catch more walleye when ice fishing in Northern Ontario.

Bear Creek Bruisers

Fishing Musky on Lake Nipissing

Walleye Fishing at Waterfalls Lodge

Waterfalls Lodge offers a wide variety of angling opportunities.

Walleye on Lake Temiskaming

Fish'n Canada heads to Lake Temiskaming to tackle Ontario Walleye.

Girls Getaway

How to Gather your Girl Group for a Fishing Trip

Pleasant Cove Resort

Setting sights on Georgian Bay Northern Pike

How the Peaceful North Changed My Life

Daydreaming for a return all year long to the North.

Top 10 Fly Patterns for Brook Trout

Learn Brook Trout Fly Pattern Choices for Surface Fly Fishing

The Muskie: A Lean Mean Fighting Machine

Ontario is the number one Muskie destination on the planet.

Big Basswood Lake Resort

Fishing for Smallmouth Bass in Algoma's Trophy Alley

Small Lakes That Fish Big, Really Big Bass

Granary Lake Retreat is one of Ontario’s hidden gems.

10 Tips For Ice Fishing Safety

Proper preparation is key to ensuring a safe day on the hard water

Summer Fishing Patterns for Multi-Species

Bob Izumi discusses tips for different species and how to catch them when summer temperatures soar.

Trophy Pike & Ribs

Fishing at Kesagami Wilderness Lodge

Steelhead Fever

Fishing in Northwestern Ontario