My answer to How are Yachts maintained in a usable state, if they aren't in use? Where are yacht usually stored?
Answer by Desmond Last:
In Sydney people sail all year round as do many other countries. If a yacht is not being used it will normally stay on its mooring or in a berth. As the owner and broker of Sydney Boat Sales I would have to look after yachts that were no longer being used.
The first and most important boat system to ensure that is maintained when a yacht is not being used are the mooring or berth ropes and fenders.
Fenders will rub and scrub the gelcoat on fibreglass yachts so they should be covered. Ropes will chafe and will need to have a chafe cover where they rub on the deck or pontoon.
Moorings must be serviced every 12 months. They should lifted out of the water and the chain shackle replaced. Pontons are normally served by the marina. But make sure the 240v power is working and the lead has enough slack for boat movement.
If the yacht is on a fixed berth remember the high and low tides at Christmas – southern hemisphere. The same for a mooring rope.
On the Yacht the most important system is the batteries. They will need to be kept charged.
Check the bilge pumps by raising the float switch to make sure they are working. You can use warning systems that will go back to your phone.
You cannot leave a Yacht for months and be secure in the knowledge all will be fine when you get back.
My advice is to get the local Marina to run out to her once a month. Start the engine and gen set if fitted, let some air in through the hatches and check the bilges.
Tip: Do not excessively idle your engine or gen set. It will glaze the cylinder walls and cause excessive blue smoke. Put her into gear at low revs and load the gen set.
Tip: If your yacht is tiller steered make sure it is securely tied up – this will stop excessive wear of the rudder bearings.
The stern of a yacht in salt water will always attract more marine growth than the port and starboard sides as the water is less turbulent there. Before you get back employ a diver to clean the prop and rudder and to clean out the engine water intake – or slip her. She may also need a seagull cleanup.
Sails should be covered to prevent sun damage. If she is a Timber Yacht I would use a cover over the whole of the deck and cabin. Still fresh water will rot the timber and the sun will cause the timbers to shrink too much.
Make sure she is securely locked up.
It is a false economy not to employ somebody to check your yacht whilst you are away.