Ireland's sailing, boating & maritime magazine

Engine health

15th October 2010
Just before hauling the boat from the water, run the engine for 10–15 minutes until it reaches operating temperature, then change the lube oil and filter, as contaminates in the old oil can cause corrosion.

Disconnect the cooling water supply pipe from the seacock. Arrange a freshwater supply from a 2–3 gallon bucket. Drain off-block and remove thermostat. Replace thermostat housing and inspect the anodes for corrosion, if fitted.

Run engine again, this time using an anti-freeze solution. Antifreeze should be at the recommended strength and, with turbo engines, ensure that the correct anti-freeze is used: the cheaper types burn off with the high temperature of turbocharging.

The fuel system should be drained of water but if the diesel filter is changed it’s possible that, on launching at the start of the new season, you’ll find the new filters have become clogged while the boat was standing idle.

Again, drain off, block and replace thermostat (clean it first). Gearbox and hydraulic systems should be checked and the oil changed if required. Flush the raw water system with fresh water, but make sure that it’s all drained off as frost damage can be a real problem.

On craft with sterndrive, bellows and jubilee clips should be carefully checked, and by servicing them now the chance of seizing is offset.

Replace the fuel filter element and, if fitted, clean out the water/dirt trap.

Fill the fuel tank to the maximum to prevent bacteria forming – ‘diesel bug’ – and to prevent condensation during the winter.

Auxiliary outboards should be taken home, serviced and stored in an upright position. If they’re stored lying on their side, water can damage the main bearings leading to nasty rumbles and expense.

Touch up any areas which need paint, grease all necessary points and spray the entire block with WD40 or it’s equivalent.

Growth and barnacles are easier to remove the day the boat is lifted. The outside should be washed with fresh water and then carefully checked for damage to the surface. Scrub the bottom of the boat to remove weed and barnacles, then inspect for cracks, blisters, rot or corrosion.

Check the sterngear for wear by lifting the shaft vertically and looking for any sign of looseness in the stern-gland or P-bracket bearings. Inspect outdrives and check on the condition of all sacrificial anodes. If there is very little change to the anodes, have the connections inspected as they should wear down. Any which are seriously eroded should be replaced. If they look shiny or have developed a pale brown colour, they are not doing their job. The most likely cause is that the electrical connection between the anode and the boat’s metal fittings has become disconnected

Check the rudder for wear in the bearings. Inspect for cracks or corrosion, particularly where it joins the shaft.

Inspect the propeller for any signs of damage or corrosion and ensure that it is tight on the shaft. Paintwork and varnish should be repaired to prevent the ingress of water. Deck fittings can gradually become loose during a season and can lead to water trickling into the interior. Clean the covers and repair any tears as winter storms can destroy a cover in an instant. Check that all cockpit drains are clear, especially the drain hole and anchor locker.
Published in Boat Maintenance Team

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