First time winterization of a small outboard

[Barrettscv]

Winter is here in Wisconsin. I put my 3.5 HP Mercury 4 stroke in the heated basement after taking the boat out of the water 4 weeks ago. The motor was new in July. It was kept on a freshwater lake from August to Oct and always ran well. I use recreational gas (no Ethanol) and added stabilizer since new.

This weekend I went ahead with the winterization, including starting the motor in a clean garbage can full of water. Once the motor warmed up, I cut the fuel supply and when the motor started to sputter, fogged the intake. (Removing the air intake box also disassembled the carburetor from the intake manifold, so I had to reinstall the carburetor without the air intake and restart the motor before I could cut the fuel and fog the intake). I also removed the spark plug and fogged the combustion chamber. I hand cranked the motor and had some fogging lubrication draining from the spark plug hole. I reinstalled the spark plug and hand cranked again. I also drained the remaining fuel from the integrated tank.

I’m reluctant to change the oil at this point, it looks uncontaminated. Are there other steps to consider?

[JoeRobertJr]

I am in the process of winterizing my 9.9 Honda outboard for the first time. I am just following the instructions in the owner's manual, which I found online.

[Pete7]

Since the engine is only a few months old, I would change the oil to remove any little pieces of metal left over during the build and any burrs on the gears etc. The drain plug for the gearbox for example, normally has a magnet on the inside to attract metal bits. Remove carefully and clean, then replace the oil in the engine and gearbox.

This assumes you paid hard earned money for it and wish to keep the engine running for some years. Mercury do a spray which I used to douse the power head each winter.

Pete

[Barrettscv]

Originally Posted by Pete7

Since the engine is only a few months old, I would change the oil to remove any little pieces of metal left over during the build and any burrs on the gears etc. The drain plug for the gearbox for example, normally has a magnet on the inside to attract metal bits. Remove carefully and clean, then replace the oil in the engine and gearbox.

This assumes you paid hard earned money for it and wish to keep the engine running for some years. Mercury do a spray which I used to douse the power head each winter.

Pete

Good point. Anything else?

[George DuBose]

For long-term storage, someone said I should pull the impeller out of the water pump.

[alansmith]

Drain the gear oil in the leg. Add fresh gear oil. You don’t need to fuss with the impeller. Pull the prop and regrease the splines. Give her a new layer of wax. Make sure your carb bowl is emptied before storing her.

[Mithril Bham]

Sounds like you are doing more than most. Change oil for sure. I wouldn't worry about impeller although new impeller every year is not a bad idea although a bit overkill. Change filters, of course. Obviously empty carb.

[Barrettscv]

Originally Posted by Mithril Bham

Sounds like you are doing more than most. Change oil for sure. I wouldn't worry about impeller although new impeller every year is not a bad idea although a bit overkill. Change filters, of course. Obviously empty carb.

I’m now planning on changing the oil, both at the motor and at the lower drive, and also change the filters.

I’m trying to decide if I should remove the carb to verify that it’s empty. This outboard has a valve that cuts fuel to the carb. I closed the valve while the motor was warm and running. A few minutes later it started to sputter. At that point I fogged the carburetor intake which immediately killed the motor. I’m wondering if the carb is totally empty.

[GordMay]

Take care of it in the fall; don’t wait ’til spring:
You could put a coat of anti-seize lubricant on the plugs’ threads before (carefully) replacing them.
Check your engine’s lower unit for water; if you find water, be sure to drain it. Water can freeze and expand during storage, potentially cracking the unit.
Change the gear lube, and replace it with fresh lube, along with new washers on the fill and vent screws. As you drain the old oil, inspect it carefully. If it’s milky, it may indicate a leak. Take your outboard to the dealer for service*.
The presence of fine metal particles (resembling powder) in the gear lube indicates normal wear. The presence of metal chips in the gear lube indicates abnormal damage*.
With some gearcases, you will have to remove the propeller in order to change the lube; but even if your engine doesn’t require that, it’s a good idea to pull the prop off anyway. Inspect it for damage and send it to be repaired if necessary. This also is an ideal time to check the shaft for debris and fishing line that might be wrapped around it, which could spoil your whole day at the start of next season.

*What do you do with a sick boat?
TAKE IT TO THE DOC!

[nortonscove]

Wow you guys are dedicated. I don't do any of this. I pulled the thing off the dinghy and put it in my unheated shed as I do every year. Changed the oil after year six.

[CarlF]

If you go south of Norfolk, it still gets below freezing but no one "winterizes" their outboards and they seem to last just fine. No need to winterize a 4 cycle engine in a car. Outboards drain of water as long as they are tilted (although I give the starter a couple of pulls to be sure). Sitting is not good for any engine. I give it a good hard run in March.

I change the oil once a year and the lower unit grease every two years. Unless you run your engine for 100+ hours in a season I don't think it much matters when you do it. With a new engine, I would change the lower unit grease after the first year.

Unlike the OP, I have ethanol in the gas so I am very careful to get the carb drained by running it out and then opening the little drain screw in the carb (a honda). I then empty the gas tanks into a car. I do this anytime the outboard will be unused for more than a month with ethanol gas. With ethanol free gas, I'd probably just leave it as long as there's stabilizer in the gas.