Winter in Mallorca is mild, but that does not mean your boat can be left alone for months. Humidity, salt and autumn storms cause more breakdowns than any summer passage. Proper winterizing costs little compared with a repair in spring, just when you want to be back on the water.
1. Change the oil before you stop, not after
Used oil contains acids and combustion residue that attack the engine from the inside during months of inactivity. That is why the oil and filter change is done at the end of the season, with the engine still warm. Check the sterndrive or gearbox oil and the coolant level at the same time.
2. Full tank and stabilised fuel
A half-empty tank fills with humid air, and that moisture condenses into water. In diesel, water encourages bacteria that clog filters and injectors. We recommend:
- Filling the tank almost to the top.
- Adding a fuel stabiliser (petrol) or a biocide (diesel).
- Draining the water separator of the fuel filter.
3. Raw water circuit: flush and impeller
Crystallised salt is the enemy of pumps, heat exchangers and exhaust elbows. Flush the cooling circuit with fresh water and check the water pump impeller: if its vanes are bent or cracked, replace it now. An impeller that spends the winter deformed usually fails on the first outing.
4. Keep batteries charged all winter
A flat battery sulphates over the winter and loses capacity for good. If your berth has shore power, leave a maintenance charger connected; if not, disconnect the batteries and charge them once a month. Clean the terminals and protect them with dielectric grease.
5. A dry, ventilated interior
Mould appears within weeks in a closed boat. Empty fridges and fresh water tanks, leave lockers ajar, take cushions home if you can and use moisture absorbers. A well-fitted cover protects the deck, but it must let air circulate.
6. Mooring lines, fenders and bilge pumps
Autumn storms test every line. Check mooring lines for chafe, add chafe guards and make sure the bilge pumps and their float switches work. A failure here can sink a boat at its berth.
A boat that is winterized properly takes half the time to prepare in spring.
Would you rather we took care of it?
Ocean Pro Nautic carries out complete winterizing in Palma and all over Mallorca: oil and filter change, cooling circuit check, batteries and a condition report on your boat. If you are away, our boat care service keeps an eye on it all winter. See our services or request a quote.
