winter engine maintenance

[osprey877]

I have a yanmar 3.gm diesel in my sailboat. I visit the boat once a week during the winter to check on it, but don'it take it out. Should i start the engine and let it run for sail20 minutes at 1000 rpm, or should i just leave it until the spring. I am in the pacific northwest so can get cold for a.week or two, but not like back east.

[Neo]

I don't have the definitive answer to that question, but if I were you and I didn't need to start the engine to charge the batteries, I would winterize it and leave it be until spring.

If I did decide to run it, I would run it at 80% of maximum rpm under load for at least 20 minutes to minimize carbon build up. Might want to double up the dock lines first.

[laika]

+1

If you were going into a cold snap you could always close off the raw water intake, take the hose off the intake side of the water pump">raw water pump, and let the water drain out (if you have the freshwater version of the 3gm).

That's what I do with mine at least. "Winterizing" is about a 2 minute ordeal.

If you're not gonna run the engine for a while, ideally you'd get some fresh fluids in there, too.

FWIW, if you're on the hard, you can run the engine and suck some non-toxic antifreeze into the raw water side to inhibit corrosion. I believe MaineSail has an excellent how-to on this somewhere out there.

[delmarrey]

Well it's been 12º F for the past three nights at my place just S. of Lynnwood.

On my 3JH I have put in a Tee above the seacock where I plumb in a hose from a bucket. For winterizing I flush the motor with fresh water until it reaches temp then add add antifreeze to the bucket. When the bucket empties I shut the motor down.

Next I close the seacock, drain the wetlift and pull the impeller from the raw water pump. I spray the impeller with silicone and put it and the coverparts in a baggie.

Then I spray the whole motor down with WD-40 or if I'm on the hard I keep a 250 watt lamp in the motor compartment to keep the motor dry.

But the boat's in SF now so it's just flushed with fresh water.

And don't forget about any other water pumps on the boat they will freeze too. I had to repair my deck washdown pump one year due to forgetfulness.

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