Boat Winterizing Checklist

MarineEngineParts.com Winterizing Checklist
Lighthouse Marine Supply, 29 Edgar Ave, Riverhead NY 11901 · 631-722-5700

Use this as the running order for winterizing your boat. Tick each line as you go and the page remembers where you were, so you can close it, walk back out to the boat and pick up where you left off. Every line links to the parts that step needs.

Working on a specific engine? The full winterization guide has a version written for Yamaha, Mercury, MerCruiser, Suzuki, Honda, Volvo Penta and Evinrude, with the oils and additives each brand calls for.

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Fresh water, salt water, air conditioning and sanitation

Anything that holds water and cannot drain itself. This is the section that cracks fittings over a cold week in January.

Empty the water tanks, drain the hot water heater and install a bypassWater heaters, bypass kits and fittings
Run non-toxic antifreeze through the fresh water lines until it runs pink at every tapNon-toxic antifreeze, -50 and -100
Pump out the head and holding tank, then winterize both with non-toxic antifreezeHead and holding tank treatments
Winterize the saltwater washdown pumpWashdown hoses and nozzles
Winterize the air conditioning pump and its raw water circuitAir conditioner pumps
Run antifreeze through the whole system until it comes back full strength, not dilutedAll antifreeze

Outdrives and outboard lower units

Read what comes out of the lower unit before you think about the refill. Clean lube is the color it went in. Milky means water got past a seal, and glitter means something inside is wearing.

Drain the lower unit oil and look at it, then refill from the bottom screw until it comes out the topGear case and transmission oils
Replace both drain screw seals and gaskets, the two dollar part everybody reuses and regretsSpecific to your engine, send us your model and we will match them
Change the water pump impeller if it is due, and buy the kit rather than the bare impellerOutboard impellers and water pump kits
Sterndrive and inboard, same job, different kitSterndrive and inboard impeller kits
Grease every fittingGreases and lubes
Pull the prop and grease the shaft, and check for fishing line behind it while it is offPropellers and hardware
Replace the outdrive, transom and lower unit anodes as neededAnodes and anode kits
Inspect the shift and exhaust bellows for cracks, and the shifter cable while you are in thereBellows are model specific, send us your drive and we will look it up

Batteries

A battery left connected all winter will find something to drain into, and a dead flat battery usually does not come back.

Take the battery off the boat and test itBatteries and accessories
Charge it and store it somewhere cool and dry that will not freeze, on a maintainer if you have oneChargers and maintainers
Clean every terminal and coat it with a corrosion inhibitorBattery terminals and accessories

Cover it so it breathes

A wrap with no vents is a greenhouse. Whatever moisture is in there in November is still in there in April, on your upholstery.

Shrink wrap or tarp it so it sheds water instead of holding itShrink wrap and tarps
Strapping, doors and vents, and the tools if you are wrapping it yourselfInstallation supplies and tools and accessories
Put moisture and mildew control inside the cabin before you close it upMildew, moisture and salt control
Blocking it on stands, or leaving it in the water with a de-icerBoat stands and dock de-icers

Whenever the engine is running, make sure it has continuous water flow.

Everything on this list is in our winterizing section. If you are not sure which product fits your engine, call us at 631-722-5700 or send us your model and serial number. We would rather answer the question than have you buy the wrong gear lube.

Fresh water, salt water, air conditioning and sanitation

Fuel and engine

Outdrives and outboard lower units

Batteries

Cover it so it breathes

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