Prepping an Outboard for Winter?

Golden Time

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I've read the numerous posts about winterising an inboard motor and everything but can't find one that's spoke about outboards.

Apart from the chemical loo, which will shortly come off the boat, there is no other water on the boat. Tap was broke and tank was manky so it's all in the shed until I decide what I'm doing.

So the only thing I have to worry about is the outboard.

The boat will be staying afloat in the Brayford Pool - which for the last two winters has frozen with a considerable layer of ice. Although I don't know if the freezing was as severe around the boats.

I've read about blocking the exhaust and the air intake and using fogging oil. But the exhaust is a through prop exhaust so will be below the waterline?

I've read about flushing the motor with fresh water, but I don't understand what benefit that would be when the motor is in the water all the time anyway (canal not salt water).

Should I just buy a can of fogging oil, disconnect the fuel line and spray the oil into the carb until it stops. Then remove the plugs and spray it in there with a couple of pulls on the starter to get a coating. Then block the air filter. That seems to be the suggestion I find most often.

Or shoud I just leave it as it is because as I've said before, I don't know the providence of the motor. Haven't got any service history or even an idea of the year as there's no paperwork. I suspect it has never been winterised before and it seems to be doing fine.

Thoughts would be appreciated. Anything that will save me money in the spring so I can get my new windows. :p
 
If you are not going to use it for a while, the idea of fogging is to stop the insides of the engine going rusty, especially on 2 smokes. Nothing really to do with the anti-freezing of winterising, we used to fog jet skis after every use, even in the Summer (not suggesting you do that with the outboard).

Flushing outboards with fresh water is done to get rid of the salt inside, again, nothing really to do with winterising.
 
I guess it also depends on if you plan on using it or not.

I have left a 2 stroke in the water (salt) over winter on the south coast, and other than starting it up and running at least once a week, it survived with no obvious problems. However, if you don't plan to use it, I would see if you can rig a bucket or a hose and fill with antifreeze mixture, than run that through the engine using flush muffs.Be sure to catch the antifreeze coming out of the tell tale though, fish don't like it very much. This is alot easier if you can get her out of the water.

I would also suggest running the engine, then disconnect the fuel and leave it running until it splutters. This will help to clear and residual fuel from the carb which can get gunky over winter if not used. Give a good dose of WD40 to most parts of the engine.

There are more things you can do, but these might be a good start
 
If you're not going to use the OB for the next few months, I'd at least change the engine oil and the gearcase oil. Yes, fogging oil is a good bet unless you're going to run the engine on a semi regular basis.

Also, from what I've read, if it's a 4 stroke, don't tilt it out of the water but leave it in its normal running position. Don't know why, something to do with the lube system on 4 strokes :confused:.

My boat is currently out of the water on its trailer until April next year and I won't be doing much more than the three things above.
 
You have not said what make and model it is or if its a 2 or 4 stroke.

The owners manual may be available on line .. if so that will give you all the details of servicing.

Basically at the end of the season give it a full service .

Plugs, points if points ignition. Clean, check, reset or replace as required

Grease all greasing points and oil or grease other external moving points as appropriate.

Check cooling water flow. If suspect or if pump impeller has not been replaced recently replace it

Fog along the lines you suggest if it is not going to be used.

Clean or replace fuel filter(s)

Drain and refill engine oil and renew filter if 4 stroke

Drain off and dispose of all fuel.
Best to transfer any fuel to be stored to suitable metal cans, treat with a f el stabiliser and store only full tightly capped cans.

Drain and refill gearcase with fresh oil. If old oil is milky rather than "clear and bright" it indicates defective gearcase seals. Investigate and replace the seals.

Check anodes.

Touch up any damaged paintwork

IMHO leaving an outboard with its prop and gearcase immersed is bad news.

Store upright protected from freezing. If it must be laid down ensure all water is drained first and if its a 4 stroke only lay it down in the way specified in the owners manual

No need for any flushing if its in fresh water anyway.
 
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I've read the numerous posts about winterising an inboard motor and everything but can't find one that's spoke about outboards.

Apart from the chemical loo, which will shortly come off the boat, there is no other water on the boat. Tap was broke and tank was manky so it's all in the shed until I decide what I'm doing.

So the only thing I have to worry about is the outboard.

The boat will be staying afloat in the Brayford Pool - which for the last two winters has frozen with a considerable layer of ice. Although I don't know if the freezing was as severe around the boats.

I've read about blocking the exhaust and the air intake and using fogging oil. But the exhaust is a through prop exhaust so will be below the waterline?

I've read about flushing the motor with fresh water, but I don't understand what benefit that would be when the motor is in the water all the time anyway (canal not salt water).

Should I just buy a can of fogging oil, disconnect the fuel line and spray the oil into the carb until it stops. Then remove the plugs and spray it in there with a couple of pulls on the starter to get a coating. Then block the air filter. That seems to be the suggestion I find most often.

Or shoud I just leave it as it is because as I've said before, I don't know the providence of the motor. Haven't got any service history or even an idea of the year as there's no paperwork. I suspect it has never been winterised before and it seems to be doing fine.

Thoughts would be appreciated. Anything that will save me money in the spring so I can get my new windows. :p

Is taking it home an option??? I keep mine in the garage over winter and get it serviced just prior to the new season....
 
Thanks for all the replies.

I forgot to say its a Honda 9.9hp 4 Stroke.

Also forgot to say that I was hoping to use the boat once or twice a month during the off season. Call it my haven away from home. LoL.

With regards to taking it off the boat that's another story. LoL. I can see how to take off the steering system and unbolt the motor from the transom. But... I can't see/don't understand how to take the throttle/gear cables or electric cables off from the motor end. I don't even think its a Honda throttle lever/cables.

Will have a longer look at how to remove it from the boat and give it the full service (well, ask the father in law to). LoL.
 
I've never heard about leaving an outboard in the down-running position when left in the water, they're all designed to be tilted up out of the water, so unless you have an oil leak of some kind, that's the best route.
When you pull up the engine into the tilt position, most of the water will just run out but in the winter I've always run an engine for about 5 seconds out of the water so the impellor will push out any excess water left in the system. If you plan to use her a few times over the winter then just leave her be but I'd suggest running her for about ten-fifteen minutes at least once every month or so just so nothing starts to corrode or seize up.
 
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