Winterizing Your Boat

When the boating season is winding down and you do not boat in a year round boating area, it’s time to start thinking about protecting your valuable recreational asset. The time and effort you spend now will have a definite effect on your boat’s performance, or lack of it, and certainly save you time, effort and money come spring. You should remember that your insurance policy may not cover damage done by lack of maintenance or neglect.

The best place for your boat to be during the winter is out of the water, under cover, in a climate-controlled boat storage area. This, however, can be expensive. If don’t have this option perhaps you should consider shrink-wrapping your boat. This, too, is a little expensive but provides a very protective cover. Short of these two items, make sure that your boat is well covered with a tarp or some other sturdy cover.

Your first step in winterizing should be to make a checklist of all items that need to be accomplished. Check the owner’s manual of both your boat and motor for manufacturer’s recommendations on winterization. If you are a new boat owner, perhaps you should employ the assistance of a friend with experience in winterizing or hire a professional to do the job. Here are some general procedures you’ll need to follow.

Inboard Engines:

  • You should run the engine to warm it up and change the oil while it is warm. This allows the oil to drain more fully. Make sure you supply cooling water to the engine via the flushing port. Remove the oil filter and properly dispose of it as well. Refill the engine, check the level and check it again for leaks.
  • Finally, flush the engine with non-toxic antifreeze by using an intake hose to the water pump. Place the end of the hose in a bucket or bottle of antifreeze. Start the engine and allow the antifreeze to circulate until it starts to exit the exhaust. While you’re in the engine room you should also change the fluid in your transmission. Remove spark plugs and use “fogging oil” to spray into each cylinder. Wipe down the engine with a shop towel sprayed with a little fogging oil.

Stern Drives: 

  • You should thoroughly inspect the stern drive and remove any plant life or barnacles from the lower unit.
  • Drain the gear case and check for moisture in the oil. This could indicate leaking seals that must be repaired before spring recommissioning.
  • Clean the lower unit with soap and water.
  • If your stern drive has a rubber boot(look between the transom and engine), check it for cracks or pinholes.
  • Grease all fittings and check fluid levels in hydraulic steering or lift pumps.
  • Check with your owner’s manual for additional recommendations by the manufacturer.

Outboards: 

  • Gauge the remaining fuel in the tank and treat it with the correct amount of a fuel stabilizer.
  • Flush the engine with fresh water using flush muffs or the flushing port usually on the back of the engine.
  • Start the engine and with it running and the cowl removed, spray fogging solution into the air intakes on the front of the engine.
  • While its still running, remove the fuel line from the engine and continue spraying fogging solution until the engine dies. It is important to run the engine with the fuel line removed to burn all fuel from the carburetors to prevent build-up of deposits from evaporated fuel.
  • Apply water resistant grease to propeller shaft and threads.
  • Change the gear oil in the lower unit.
  • Lightly lubricate the exterior of the engine or polish with a good wax.
  • Wash the engine down with soap and water and rinse thoroughly

Fuel: 

  • Some manufacturers suggest filling your fuel tanks and adding stabilizer to the fuel. Full tanks leave less room for condensation to form.
  • Other manufacturers, noting that ethanol may spoil over the winter no matter what you do to it, suggest just adding fuel stabilizer. If the fuel is is spoiled over the winter, there is less to drain and dispose of.
  • Change the fuel filters and water separators.

Bilges: 

  • Use soap, hot water and a stiff brush to clean up any oil spills.
  • Once the bilges are clean, spray with a moisture displacing lubricant.
  • Add a little antifreeze to prevent any water from freezing.

Fresh Water System: 

  • Completely drain the fresh water tank and hot water heater.
  • Isolate the hot water heater by disconnecting the in and out lines and connect them together.
  • Pump a non-toxic antifreeze into the system and turn on all the facets including the shower and any wash-down areas until you see the antifreeze coming out.
  • Also put non-toxic antifreeze in the water heater.

Head: 

  • Pump out the holding tank at an approved facility.
  • While pumping, add fresh water to the bowl and flush several times.
  • Use Vanish crystals or whatever your owner’s manual recommends that will not harm your system and let sit for a few minutes.
  • Add fresh water and pump out again.
  • Add antifreeze and pump through hoses, holding tank, y-valve, macerator and discharge hose.
  • Again, check your owner’s manual to make sure that an alcohol-based antifreeze won’t damage your system.

Interior: 

  • Once you have taken care of the system you should remove any valuables, electronics, lines, PFD, fire extinguishers, flares, fenders, etc.
  • Over the winter these items can be cleaned, checked and replaced as necessary.
  • Open all drawers and lockers and clean thoroughly.
  • Turn cushions up on edge so that air is able to circulate around them or, better yet, bring them home to a climate controlled area.
  • Open and clean the refrigerator and freezer.
  • To keep your boat dry and mildew-free you might want to install a dehumidifier or use some of the commercially available odor and moisture absorber products such as “No Damp,” “Damp Away” or “Sportsman’s Mate.”

Out of Water Storage: 

  • Pressure wash hull, clean barnacles off props and shafts, rudders, struts and trim tabs.
  • Clean all thru-hulls and strainers.
  • Open seacocks to allow any water to drain.
  • Check the hull for blisters and if you find any that should be attended make a note to tell your service manager.
  • Now is a great time to give the hull a good wax job.
  • Be sure the batteries are fully charged and switches are turned off.

In Water Storage:

  • Close all seacocks and check rudder shafts and stuffing boxes for leaks, tighten or repack as necessary.
  • Check your battery to make sure it is fully charged, clean terminals, add water if necessary and make sure your charging system is working.
  • Check bilge pumps to ensure they are working and that float switches properly activate the pumps and that they are not hindered by debris.
  • Monitor your boat regularly to avoid leaks, or animal infestations.
  • If your mooring area is likely to freeze be sure to suspend water agitators below it to bring warmer water to the surface so its not iced in.

By following some of the above suggestions, and suggestions given from the links provided, you should be in good shape for the winter. Do not, however, neglect to consult your owner’s manuals for manufacturer’s recommendations on winterizing your boat and other systems. If you have not done a winterization job before, or don’t have an experienced friend to rely on, seek out a professional to do the job for you.