Early spring: Are you still screwing? The last-minute check

All topics of this season start special:

• Renew antifouling
• Servicing the steering gear
• Correct polishing of hull and deck
• Check rig and mast and trim correctly
• Maintenance of deck fittings and winches
• Check and repair sails
• Safety equipment check
• Engine and outboard motor maintenance
• Last-minute check on a weekend

1. check batteries

Why is it so important?
Flat or faulty on-board batteries are one of the most common causes of frustration during the first test run in spring. A deeply discharged battery can quickly become irreparably damaged.

What needs to be done?

• Lead batteriesHave they been disconnected in winter and stored in a cool but frost-free place? Then charge them fully before fitting. AGM batteries can withstand deeper discharges better than gel batteries, but they should not fall below 50 per cent.
• Lithium batteriesIn winter, only charge to around 1/3 to 2/3 of capacity, as they are unnecessarily stressed in the upper range. Avoid permanent connection to a charger at all costs in order to extend the service life.
• Spring checkClean the poles, check that the pole terminals are firmly seated and repair any corrosion. If you have installed new consumers during the winter season, you should now check all cable connections and cross-sections: Avoid fire hazard!

More about batteries:

• Comparison of lead and lithium batteries
• Ingenious! Combining lithium and lead
• Lithium batteries: now also for bow thrusters and anchor winches
• Converting to lithium batteries: how it works
• The alternator delivers more power with little effort

2. check the diesel pest

Why is it so important?
When microorganisms grow in the diesel, sludgy deposits form. These can clog filters and injection nozzles and cause the engine to fail. The problem often occurs when condensation has formed in the tank or biodiesel has been refuelled.

What needs to be done?

• Refuelling checkIs there an inspection cover on the tank? Then check the tank for water residue and dirt. Does the diesel smell musty or is there a slimy film on the tank cap or the tank itself?
• Acute case: Siphon off or drain off water and diesel sludge, replace fuel filter and take reserve filter on board. Shock dosing of additives is usually not sufficient.
• Water separatorIf not already fitted, retrofit. This prevents water from collecting in the fuel system.

More on the diesel plague:

• Biodiesel HVO100: No more diesel pest
• What helps against the diesel pest in the fuel tank
• Four practical tricks for clean diesel and cooling water
• Avoiding trouble: maintaining the diesel engine during the season

3. check the cooling circuit

Why is it so important?
A functioning engine needs a free flow of cooling water. If the system is blocked, there is a risk of serious engine damage due to overheating.

What needs to be done?

• Check seacocksCheck for damage or fouling (e.g. mussels, barnacles) while still on land and open the valves.
• Hoses & clampsReplace cracked or porous hoses, always replace corroded hose clamps - (!) always use two clamps.
• Test in waterIf the engine is running, water must come out of the exhaust immediately (or be visible in the seawater filter). If this does not happen, switch off the engine and check for a blocked seawater filter or blockages in the intake or a defective impeller.
• Flush outboard motor: A flusher can be used to flush the cooling water after the winter. This prevents dirt from settling permanently and keeps the engine clean from the inside.

4. check the side outlets

Why is it so important?
Seacocks and through-hull outlets are potential weak points for water ingress. Frost can cause damage, especially if water has collected in them over the winter. Be sure to check the tightness of the outlets while still in the harnesses!

What needs to be done?

• Recognising frost damageOpen and close the valves before adding water, check for cracks or leaks.
• Scratch testScratch carefully with a screwdriver. If the area appears reddish or crumbly, this indicates corrosion.
• Maintenance & replacementIn doubt? Better to fit a new valve (or have one fitted). Grease regularly and check for free movement - preferably twice a year, when winterising and winterising.

5. change anodes

Why is it so important?
Sacrificial anodes protect the propeller, shaft, saildrive and other metal parts from corrosion. If they are used up, they no longer work properly - and expensive components can suffer.

What needs to be done?

• Check conditionAre the anodes stuck, are they largely dissolved or still fully intact?
• Choice of materialZinc for salt water, magnesium for fresh water. Those travelling in brackish waters often use aluminium anodes as a compromise.
• Create planNote all anode positions (including those in the cooling circuit) so that no point is forgotten during the next spring check.

6. check outer skin

Why is it so important?

Moisture can penetrate through hairline cracks in the gelcoat. Moisture can damage the laminate in the long term.

What needs to be done?

• Visual inspectionIs there any damage to the gelcoat?
• In acute casesSeal hairline cracks, if necessary find out the cause with a specialist
• Cleaning and polishingAvoid new soiling and protect the surface
• Check antifouling: Remove barnacle residues, check the condition of the paint and renew. Ensure compatibility with the old coating
• Folding propeller: if necessary on Check function
• Anodes: Do not paint over with antifouling

7. check rig

Why is it so important?

The rig is a wearing material and a broken mast can seriously jeopardise the ship and crew. Sailors are advised to check their rigging every winter. Checking is best done while the mast is still in place.

What needs to be done?

• Check current goods: Are the traps running clear?
• Check the standing crop: Wires coming loose from the terminals. Do cotter pins secure all bolts? Are the shroud tensioners working properly?
• Commission specialists: Do you notice wear, corrosion or cracks? Call in a rigger. Commission specialists on a regular basis. Trained eyes detect faults early and protect against hazards.

More about the rig:

• Rig check: What owners should look out for before setting the mast
• Rig check at the start of the season: maintaining the rig properly
• Rig trim: The trim guide for the right tension in the rig
• Maintenance intervals: how often the rig and co. need to be checked
• Perfectly adjusted mast - tips from sailing pro Tim Kröger

Conclusion: One weekend is enough - if you know what's important

Winterising a boat means more than just getting it out of winter storage and into the water. If you only have a weekend, prioritise the main sources of danger.