Below is a very simply guide to servicing/winterising your outboard. Do this after season's use to ensure your motor will be ready for the Next season

Step 1

For smaller outboards, the simplest way to flush your outboard is by using a large bucket of water. Be sure the bucket is large enough to completely cover the water intake ports on the lower unit of the outboard. Also be sure that the bucket is wide enough so that no part of the motor will touch the sides/bottom of the bucket. Securely mount your outboard on a sawhorse or some other type of apparatus that will allow safe operation of your outboard.

With the 5-140 hp you can either use the optional “flushing plug” which can be attached to a hose for flushing the engine with fresh water or purchase a set of “flush muffs” (available at your local marine dealer). This equipment attaches to your garden hose and clamps on to your outboard's lower unit, covering the water intake ports. Turn the garden hose on full before starting your engine.

Run your outboard at normal idle speed for 5-10 minutes to allow the engine to warm up and to ensure your outboard is thoroughly flushed with clean water.

After flushing the outboard, allow the water to completely drain from the engine (see Step 2 before you shut off your engine). Your outboard should be in a vertical position for the water to completely drain. While you're waiting for your engine to drain, wipe off any dirt, grease, etc. from the exterior of the engine.

Drain all fuel from the fuel hoses, fuel pump and carburettor.

When you have completed the fresh water flush in Step 1, disconnect the fuel line at the motor and continue running the motor until it runs out of gas. It is extremely important to ensure that all of the fuel has been drained from the carburettor otherwise any fuel/oil mixture remaining will evaporate and leave deposits (also called varnish, gum, etc). in the carburettor.

To drain the fuel from the carburettor you can use one of these techniques:

If you have fuel left in your tank you may want to add some fuel stabilizer to it, so that it can be used the following season. Fuel stabilizer will also help prevent condensation from forming in your fuel tank.

If your outboard is not an oil-injected model (i.e. you mix your gas/oil manually), I highly recommend you do not store the fuel for extended periods of time. Over time, the gas and oil will separate which will lead to a lack of lubrication to your engine from using a now incorrect pre-mix.

Treat your outboard with “storage oil” (also called “fogging oil”).

Storage oil comes in an aerosol spray can and is used to prevent rust on the engine's cylinder, crankshaft, bearings, pistons, etc. and can be purchased at most local marine dealers. Follow the oil manufacturer's recommendation on the amount of storage oil to use (generally about 2 ounces for each cylinder).

First, remove the spark plug (s) and the stop switch lanyard cord from your outboard. It is also a good idea to disconnect the spark plug wires from the spark plugs to prevent accidental starting.

On manual start outboards - Slowly turn the engine over a few times using the pull cord while spraying the storage oil into the spark plug holes.

On electric start outboards - Be sure you have water hooked up to your water intakes before turning over your outboard to prevent damage to your water pump. While spraying the storage oil into the spark plug holes, turn the engine over in 5 second bursts using your electric starter. Do not over “crank” your engine or you could damage the electric starter.

Apply water resistant grease to propeller shaft. Using a wheel bearing grease (or something similar), thoroughly grease the prop shaft and prop shaft threads.

Change the gear oil in the lower unit (see my other guides)

Apply water resistant grease to all moving parts, joints, bolts, nuts, and plastic fittings

To help keep your factory finish looking new, apply a light coat of oil to the exterior. Or you can also wax the exterior of your outboard using a high grade automobile wax.

Store the engine vertically in a dry area. If you store your boat in the water there are several schools of thoughts regarding whether you should store your engine in or out of the water. There are advantages and disadvantages of both ways and unfortunately there is no one “correct” or “best” way. Numerous factors such as temperature, salt/fresh water, algae growth, corrosion, etc. must be taken into account when deciding whether to leave your outboard in the water or tilt it up out of the water. Also consider if your mooring is tidal.

To find out which is “best” for you ask your local marina, other boaters in your area, etc. how they store their boat/outboard during the off-season