Checklist for Winter Boat Storage

The following are general guidelines. Check your owner’s manual for manufacturer’s recommendations/procedures particular to your boat.

Also, double check that your insurance policy will cover damage caused by freezing if your vessel wasn’t professionally prepared for winter storage by a certified marine mechanic or marina.

Following these fall storage steps now will increase your changes of a smooth a spring commissioning.

INBOARD ENGINES

• Change oil & oil filter
• Flush engine with fresh water, check for debris and unclog all drain holes
• Circulate antifreeze through the manifold
• Change transmission fluid
• Remove spark plugs/spray fogging oil into each cylinder (Gas engines ONLY)
• Wipe down the engine

STERN DRIVE

• Inspect stern drive/remove any plant life or barnacles
• Drain gear case and check for excessive moisture in the oil
• Clean lower unit with soap & water
• For units with rubber boot: Check rubber boot for cracks or pinholes
• Grease all fittings
• Check fluid levels in hydraulic steering or lift pumps

OUTBOARD ENGINES

• Flush engine with water; drain completely
• Wash engine with soap and water
• Disconnect fuel hoses; run engine until it stops
• Ensure all fuel is drained from carburetor
• Lubricate cylinder walls and pistons with fogging oil
• Apply water-resistant grease to propeller shaft and threads
• Change gear oil in lower unit
• Lubricate engine exterior or polish with a good wax

JET-DRIVE

• Flush engine with water; drain completely
• Remove all drain plugs and allow trapped water to escape
• If specified by the manufacturer, fog the engine or add the recommended corrosion protection
• Change the engine oil and filter
• Inspect the impeller, wear ring and intake grate. Remove debris and check for damage.
• Lubricate steering, reverse-gate and throttle/linkage components as recommended.

Never assume the jet-drive system has completely drained. Consult your owner’s manual for the exact procedure for removing trapped water and protecting the pump and cooling system from freezing.

BILGES

• Clean & dry
• Clean any oil spills with soap & hot water
• Once dry, spray with moisture-displacing lubricant
• Add a little antifreeze to prevent any water from freezing

FUEL

• Fill fuel tank
• Add fuel stabilizer
• Change fuel filter(s) and water separator(s)

FRESH WATER SYSTEM

• Drain fresh water tank and hot water heater
• Isolate hot water heater by connecting the in and out lines together
• Pump non-toxic antifreeze into the system and turn on all faucets/shower/wash down areas until antifreeze starts running out
• Put non-toxic antifreeze in the water heater

HEAD

• Pump out holding tank; while pumping add fresh water to the bowl & flush several times
• Add manufacturer-recommended marine cleaner/deodorizer; let sit a few minutes, then add water and pump out again
• Add antifreeze and pump through hoses, holding tank, y-valve, macerator & discharge hose

INTERIOR

• Remove valuables, lines, PFDs, fire extinguishers, flares, fenders, etc.; clean, check and replace as necessary
• Open all drawers/ lockers and clean
• Turn cushions on edge so air can circulate around them or store in a climate controlled area
• Install a dehumidifier or use an odor & moisture absorber to keep your boat dry and mildew free

ELECTRONICS

• Remove portable electronics such as GPS units, chartplotters, VHF handhelds, fish finders should be stored somewhere dry and temperature-stable.
• Remove batteries where appropriate and follow the manufacturer’s recommendations, especially for lithium batteries and electronics with internal backup batteries.
• Protect installed electronics by covering displays and equipment to keep out moisture, dust and condensation. Avoid airtight covers if they can trap moisture.
• Disconnect power if recommended — Turn off and disconnect electronics according to the manufacturer’s instructions.
• Protect connectors and wiring by checking for corrosion, cleaning connections and ensuring cables are dry before storage.
• Use moisture absorbers: Place marine-safe moisture absorbers or desiccants throughout the cabin and enclosed spaces.
• Check manufacturer instructions — Some electronics can remain aboard in freezing temperatures, while others have specific storage-temperature limits.

OUT-OF-WATER STORAGE

• Pressure wash hull, clean barnacles off props and shafts, rudders, struts and trim tabs
• Clean all through-hulls and strainers
• Open seacocks to drain water
• Check hull for blisters; attend to any you find
• Wax hull
• Take batteries out of boat; put on trickle charger or charge them every 30–60 days

Courtesy of Discover Boating.

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