I’ve been advised of the things I need to do to winterize my medium-sized two-stroke outboard (70 horse Johnson) since moving to a location where that matters (Seattle, where the average low temperature doesn’t even fall below freezing, but it does get down to freezing on occasion): fog the cylinders, stabilize the fuel, and replace the gear oil. Last year was the first year I needed to do them, and, well, I didn’t.
So the question is: just how screwed am I? It is trailered and hasn’t been started in over a year, so what kind of damage has been done already, and what kind of damage might be done by starting it now? I want to go ahead and do the winterization this time, but is there anything else I should do beforehand? My plan was 1) dispose of the old fuel and replace it fresh. 2) hook up the hose-flush thingamabob and fire up the engine for a minute, 3) go ahead and follow all the normal winterization tasks. Better advice?
My personal belief is that in our area not much needs to be done to “winterize” an outboard engine like you describe. How or where is the engine stored? If it is indoors in a garage or the like? The practical question that I ask most people with my professional hat on is " how often do you winterize your Lawn mower?" the steps are much the same, and again around here most don’t. Let me break them out one by one
Flushing the engine, practical after every use if used in seawater, on one of my outboards Yamaha 8hrs 4 stroke on a sailboat in the sound, it gets flushed after every trip away from the dock, and it has a handy built in flusher I just screw a hose into. If it is fresh water use exclusivly then not so much a need for this step. If it will be outside and exposed to really cold weather, flushing with Pink Glycol antifreeze can be helpful but can be a bit challenging to do for an outboard without the right tools (tank to put antifreeze in that the motor flusher will draw from)
Fogging is spraing a fine mist of oil in the cylinders to displace the air and any moisture in the cylinders, this is a preventative maintence thing not just for winter but for long term storage. As the engine sets the cylinder walls have potential to rust.
stabilizing the fuel, again I use the lawn mower analogy, I don’t stabilize the fuel in my lawn mower or in the tanks on my boats, but what I do, do is to top them off to full. A empty or half empty tank can be a bad thing, espeacially in a damp air enviroment. A tank with space in it gives opportunity for condensation to collect and as a result more water ends up in the tank, bad for gas engines dubbly bad for Diesel, the stabilizer can be a good ounce of prevention, add it to the tank before you top it off to full to make sure it gets mixed well. The stabilizer will help prevent the fuel from breaking down and “varnishing”. It is important to run the stabilized fuel through the fuel lines and through the engine.
Gear Lube, or Lower unit oil, again this is just a preventative maintence task, it makes sense to do, while you are doing all the other things for winter maintance. You should change the lower unit oil once a season to get the maximum life out of the equipment.
If you have any other questions I would be happy to answer them, looking for pricing or a place to have the work done I can point you in that direction too. All of these task should be able to do without outside assitance if you remotely handy.
I would not use the old gas. It gets old and varnishy and your carburator just won’t like it. And I would not risk my carb. No way.
The rest of the engine is likely to be just fine. Inspect it, maybe swap the plugs out and don’t use old gas.
Before starting, if you do nothing else, use fresh gas, then you should take the plugs out and maybe spray in some cleaner, then crank it to expel any moisture that will foul the plugs.
Phil and Skipper pretty much have it down pat, but here in New England where salt is in the water, the air and on the roads during winter one must completely climate control their rig if they want to start up fresh with no problems in May.
I have a grady marlin with an inboard, so I have a little different maintenance than with a traditional outboard. I drain all fuel, fog, unplug the spark plugs, put cotton wadding in the female plug couplings to reduce corrosian. Then I take the prop off and have it vaccum sealed.
always run in fresh water, although the garden hose flush is really easy to do (I have the little slip-on intake earmuff garden hose thingy).
it’s kept outside, covered.
For what it’s worth, the lawnmower is a terrible analogy. First, yeah, I’ve never winterized a lawnmower, but hey, it’s not exactly a high performance engine. As long as it starts and runs for 10 minutes without exploding, it’s doing its job. Second, screwing up the maintenance on my lawnmower is going to cost me the price of a new lawnmower, max. Third, I keep my lawnmower indoors. And fourth … I have an electric lawnmower.
From this wording I can’t tell if you mean to do all this before starting it, or to start it using fresh gas, then take the plugs out, etc and crank it again. Can you clarify?
One more question (maybe Skipper Too has some local advice on this one): what do I do with the old gas?
I don’t have a suggestion on disposal of old fuel. What kind of quantity are you talking about and how old is it. I have not had any issues when I have kept the tank full and used a stabilizer. Do you have more than one tank available? If you have good fuel filtration (Spin on style braket mounted canisters) Top the tank off, add some treatment, Golden Eagle’s Stabil, Starbrite’s Fuel storage Additive, Sierra’s Fuel Storage Additive, or some other brand (usally 1 oz to 5 gals of fuel) and use a little at time with “good” fuel during the season. What does the most damage, either in an outboard, inboard, or small lawn equipment is when one treats the fuel for storage in the tank but not in the equipment itself, run the stabilized fuel through the engine, with outboards it is easy to run the engine “out of gas” too, simply pull the fuel line and let it run till it dies, any fuel left in the line in theory should be treated with that method.
If the gas is premixed with 2 cycle oil and you have gas powered garden tools that could be a direction to go as well, I know you mentioned you have an electric lawn mower, maybe a neighbor could use the premix in a weed wacker, blower, or edge trimmer. IMHO Gas is best disposed of by being used, but if you don’t feel that is a wise option you can dispose of it through some county transfer stations King County Solid Waste you mentioned you are in the seattle area, the link is for what is accepted at the hazardous waste drop off/transfer stations in King County.
I think Philster is reffering to what to do in the spring when you go to use the engine again, start with fresh gas, then if you can’t get is started then pull the plugs displace any potential moisture, wash rinse repeat.
Hope that helps some, sorry if my lawn mower analogy didn’t make sense to you.
Forgot to add that you should notice that if you take gasoline to the transfer station you have to leave the container, so don’t bring it in the fuel tank you want to use in the boat.
Take out the spark plugs. Leave them out. Using fresh fuel in the tank, and maybe some engine cleaner straight into the open cylinders, crank the engine, and then any moisture that condensed (condensated?) in the cylinders can be flushed out.
It’s nice to put the new plugs on, or the cleaned up old plugs, knowing the cylinders are clean and that you won’t be fouling them for nothing.
One more thing. Seal off the open hub of the prop. Various critters can get in there, but mainly, in cold places, rain gets into the (usually) tilted-up prop and fills up the exhaust passage. When a freeze comes, the ice will expand and crack your expensive bottom casting. You can use a plastic bag. Or, even more clever, the plastic cap of several brands of canned peanuts snaps right on.
Thanks for all the advice. Regarding the amount of fuel, it’s probably less than a gallon in the bottom of the tank. I guess topping it off and adding stabilizer would be the most cautious approach, right? As far as safety goes, I’m led to believe that a mostly empty tank full of fumes is more dangerous than a full tank.
Well, maybe. If you completely fill a boat tank, there’s two possibilities. One is that there’s very little airspace (headroom) left, which means very little possibility for water condensation. That’s good. The other is than you have filled all the available space with gasoline. That means, when the temperature rises, gasoline will either squirt into the engine (a possibly harmful thing) or squirt into the space around the tank (a fire hazard thing.) Most boat fires happen right after fueling, and that’s part of the reason.
First, yeah, I’ve never winterized a lawnmower, but hey, it’s not exactly a high performance engine. As long as it starts and runs for 10 minutes without exploding, it’s doing its job. Second, screwing up the maintenance on my lawnmower is going to cost me the price of a new lawnmower, max. Third, I keep my lawnmower indoors. And fourth … I have an electric lawnmower. 