How do you hibernate a sailboat

12 nautical miles logbook

The sailing season is slowly but surely coming to an end and we hope that you have had many wonderful hours on the water this year. But before the start of winter, as every year, there is still something to do: The boat must be made winter-proof so that the next year on the high seas will be just as successful as this year’s. Anyone who has already enjoyed wintering knows how time-consuming this procedure can be. To make it easier for you to prepare for winter, we would like to give you an overview of the most important points on wintering.

A practical winter festival checklist with all the important points can be found at the end of this blog post.

1. Motor
2. The water system
3. Cleaning and maintenance
4. Anchor
5. Batteries
6. Other winter preparations
7. Checklist

1. The engine

Change engine oil and oil filter

The engine oil and the oil filter must be replaced at least once a year. It is advisable to do this before overwintering, as the acids contained in the used oil attack the metal of the engine, especially if the engine is not used for a long time. Furthermore, the oil filter should be changed, the purpose of which is to remove dirt and soot particles from the oil. If you drive little, it may be enough to change the filter every two years. The oil change is best done with the boat still in the water. Let the engine warm up for a few minutes and then use an oil suction pump to suck off all of the oil through the tube of the oil dipstick. Only then should you change the oil filter. To be on the safe side, something should be placed under it, as the oil filter can drip. Also check the filter sealing rings. When the oil and filter have been changed, start the engine again. Both the old oil and the old filter should be disposed of professionally.

Winterize the engine
At a Single-circuit cooling system let the engine warm up in the water so that the thermostat opens and the antifreeze is distributed throughout the engine. When the engine is warm, the sea cock is closed and the engine is switched off. Now the antifreeze can either be poured directly into the seawater filter or, alternatively, filled into a bucket, from which it is sucked into the engine via a suction hose. Now the engine is switched on again and is left on until colored water comes out of the exhaust. A bucket should be placed underneath to protect the environment. When it comes to having an engine Dual-circuit cooling the inner circle must also be filled with antifreeze.

Choice of antifreeze
Frost protection is available in Germany in the colors green, blue and red. The different colors result from the different mixing ratios of the components. All red or reddish coolants are silicate-free antifreeze. We recommend silicate-free Antifreeze, as silicate attacks the rubber seals and thus shortens the life of the engine.

The Impeller should be replaced at least every two years. We recommend expanding this in winter. In spring, however, a new seal for the pump housing is often necessary. Check that Air filter for soiling. If it is dirty, remove it and clean it with petrol. The V-belt drive the alternator and the cooling water pump. These should be checked regularly for cracks and fraying and replaced if necessary. Further information on tensioning the belt can be found in the operating instructions for the motor. It is also useful to keep the boat in winter storage to fill up with fuel. Thereby there is less air in the tank, so that there is no condensation that could freeze. It is also beneficial to keep the boat engine on during the winter ventilateso that no mold forms. To do this, leave the hatches and doors open to prevent the formation of condensation.

2. The water system

Winterize the water tank
Before the onset of winter, the water tank must be drained and cleaned to prevent damage from frozen water. Also remember to drain the boiler; this usually has its own indulgence. Also check the tank and the pump to see if there are any other drain valves and don't forget the outdoor shower. After draining the water, fill the tank with a non-toxic antifreeze, which is explicitly suitable for use in drinking water systems, and then let the water run until the colored water runs out of the taps. To be on the safe side, leave the taps open. This allows any residual water to expand when it freezes without causing damage.

Prepare the on-board toilet for winter
The holding tank must also be protected from frost damage. To do this, the tank is first emptied and cleaned. Then antifreeze is poured into the toilet. Now pump until the liquid comes out of the discharge. It is important that the liquid is distributed in the pump.

3. Cleaning and maintenance

To prevent damage from mold and frost, it is important to have the bilge to bilge. To do this, first remove the oil residue and then the remaining water. Special oil binding cloths are very suitable for this. After the boat has been taken out of the water, the winches can be cleaned and greased. Also, remove algae and clams from the underwater hull. A high-pressure cleaner is suitable for this. Clean that propeller, because heavily overgrown propellers lose a lot of their power. Take the opportunity to do that Underwater ship check for damage. Minor damage to the fuselage should be repaired with a special filler. If the antifouling is already showing intensive wear and tear, it is advisable to renew the paint in order to ensure greater protection against the weather in the winter season. Make sure to use an antifouling that can be applied a few months before the next watering.

4. Anchor

Both the Anchor locker as well as the Anchor chain should be cleaned of dirt and salt residues. This also works best with a high-pressure cleaner. It is also advisable to check the chain, swivel shackle and cord and replace them if necessary. In addition to the anchor locker and chain, the windlass should also be cleaned and also greased.

5. Batteries

Cold and standing in an empty state can enormously reduce the performance and service life of a battery. That is why the boat batteries should be hung on a modern trickle charger in the warm during the winter months. If this is not possible due to the weight of the battery banks, the boat can remain connected to shore power. All other circuits should be turned off. If there is no access to shore power, only fully charged batteries should be left on the boat, as discharged batteries can burst if the frost is too severe. You should therefore play it safe and clean the batteries around the poles to prevent leakage currents and the resulting discharge. Another tip: Before disconnecting, take a photo of the battery so that you can see the connections. So in spring you will have no problem figuring out how to connect the battery.

6. Other winter preparations

Winter storage in the water
If you have decided on winter storage in the water, there are a few more details to consider. If possible, slip or crane the boat before the winter season so that you check it for damage to the hull and that it is sufficient Antifouling paint can worry. If necessary, also renew the Sacrificial anodes. Close all sea valves, frost-protect the water systems and build sail and cordage to store them dry. Also the Interior must be cleared out and stored dry. Also make sure that the Mooring lines. Our tip: double this to secure it against chafing and slipping. If possible, check on the boat regularly; especially after storms or very cold periods.

Cover with tarpaulin and final steps
Make sure pad and mattresses or remove them. Furthermore, should Books and the Rig to be taken ashore. Before you leave the deck, all you have to do is get the gas bottle can be safely removed and stored. Check your tarpaulin for damage and repair it if necessary. If the boat is outside in winter storage, a good tarpaulin that can withstand wind, rain and snow is a good choice. The tarpaulin must be large and wide enough to be able to tie it underneath. Make sure that the tarpaulin is lashed sufficiently so that the wind has as little contact surface as possible. At the same time, however, sufficient ventilation should be ensured so that mold does not stand a chance. We recommend a tarpaulin with a fabric thickness of 150g-250g / sqm.

Now that your boat is well packed, all you have to do is wipe the tear from your eyes and look forward to the next year. Until then, you will find all sorts of products in our shop with which you can equip your boat.



7. The checklist: all important steps in a nutshell



  • Change engine oil and oil filter
  • Winterize the engine (frost protection)
  • Check impeller & replace if necessary
  • Check the air filter for dirt and clean it if necessary
  • Replace the V-belt if it is cracked or frayed
  • Fill up
  • Leave hatches and doors open for ventilation


Water system

  • Drain & clean the water tank
  • Drain the boiler
  • if necessary, drain other valves on the tank and pump
  • Don't forget the outdoor shower!
  • Drain and clean the holding tank
  • Important: Supply each tank with antifreeze


Cleaning and care

  • Bilge bilge
  • Clean and grease winches
  • Remove algae and mussels from the hull (tip: high-pressure cleaner)
  • Clean the anchor chain & anchor locker from dirt and salt residues
  • Check chain, swivel shackle & rope
  • Clean and grease the windlass
  • Clean the propeller
  • Renew underwater paint (antifouling)


Other winter preparations

  • to charge the battery
  • possibly disconnect the battery & hang it on the charger at home
  • Renew sacrificial anodes
  • Store sails and ropes in a dry place
  • Set up or clear up cushions and mattresses
  • Clear out books and other interior furnishings
  • Clear out the rig
  • Empty the gas bottle
  • cover with tarpaulin


Make useful products winterproof

You can now download the checklist and the infographic. For direct download click with the right mouse button and select "Save target as" and then the target folder.

This entry was posted in Boat Accessories Selection Help and tagged antifreeze, oil change, tarpaulin, overwinter, winterproof by Holger. Permanent link to the entry.