Assessing how much maintenance a boat will need – and the costs associated with expensive items that require periodic replacement – can be a challenge for anyone, especially those who are new to boat ownership.

Regular and consistent boat maintenance is the key to owning a boat that is safe and reliable, has a minimum of unexpected repair bills, looks good and retains its resale value. Whatever the vessel, it’s a continuous process requiring a constant eye on anything that may need attention, including fittings, chafe in ropes, sail damage and so on. That doesn’t mean that this aspect of maintenance has to be an onerous chore – it’s more an attitude of mind to look for the first sign of any problem and then monitor wear.

Yacht laid up ashore

Protect your investment and minimise expenditure by staying on top of your boat maintenance.

The old adage that ‘a stitch in time saves nine’ is just as applicable today as when the sailing ships carried the world’s trade around the oceans. This is especially true of mechanical and electrical systems and anything that may allow water to penetrate into the structure of the vessel, such as leaky deck fittings.

Fibreglass mouldings

A regular polish and wax will help to keep these looking like new and is especially important for deep colours, which tend to fade relatively quickly. Large areas on badly faded topsides are best done with an electric polisher.

Periodically check fibreglass mouldings for scratches, chips, stress cracks and other gel coat damage. Any cracks should be investigated to see how deep they penetrate, using a sharp chisel to open the crack into a v shape – if it does not extend beyond the gelcoat, a cosmetic repair of the gel is all that is required. However, if damage extends into the laminate below a professional repair will be needed. Also read about how to deal with fibreglass deck leaks.

boat maintenance: Yacht ashore awaiting re-application of antifouling

When doing regular tasks - like stripping, repainting and antifouling, you have an ideal opportunity to check for problems.

Looking after timber

Teak decks on fibreglass or metal boats have a limited lifespan and replacement is expensive – any signs of loose caulking, split planks or leaky deck fittings should be attended to immediately to prevent water getting under the deck. Much of the damage to such decks is the result of scrubbing with a stiff brush, which can wear up to 1mm per year from the timber. A soft brush, used gently across the grain when washing decks will avoid this wear, with the timber gradually acquiring a natural silvery appearance.

Wooden boats are at risk of damage caused by failure of the paint, varnish or epoxy coatings and the ravages of freshwater and frost. Salt water, on the other hand, is a mild preservative, so most problems are found where rainwater is allowed to settle, with any damage in the protective coatings enabling rot to take hold.

Lack of ventilation is the other key enemy of wooden structures. Dinghy covers should be made of a breathable material and yachts need a good flow of air through the accommodation areas and locker spaces, unless they are equipped with a marine specification dehumidifier. Indeed, this should be a priority on any boat, to prevent it becoming stale, damp and mouldy. The difference with a fibreglass vessel is simply that the structure won’t deteriorate, although soft furnishings and anything stored on board will certainly suffer if the interior is allowed to remain damp. For more details on this, read how to care for teak decks.

Engines and other systems

Diesel inboard engines need an annual service including changing oil, oil filter and fuel filters. Ideally this should be carried out before the winter lay up and the engine winterised at the same time. Daily checks include drive belt tension and condition, an examination of all wiring and pipe work to check for loose connections and chafe, and sump oil level and coolant level in the heat exchanger of fresh-water cooled units.

Winches being serviced

Service winches at least once a year.

Sacrificial anodes should be replaced when they are approximately one-third degraded. In practice, this often means annually. Examine the outer edges of the propeller blades for damage – surface pitting, accompanied a pinkish discolouration, is a sign of electrolytic action and should be investigated further. Also, check the cutless bearing in the P bracket for wear – it should be a snug fit around the shaft.

Damage to metal through-hull fittings is often caused by electrolysis – a white powder inside the hull around the fitting is a sign of dezincification and the fitting should be replaced. In any case, check all seacocks operate freely, and grease them before launching. Also, check log and depth-sounder transducers for damage.

Bilge pumps (and heads pumps) need periodic servicing. This may not be necessary annually if they are only used occasionally, but should be carried out every second year. Flexible gas pipes have a five-year lifespan, but if they show any signs of perishing, or if braided outer cores are starting to fray, they should be replaced immediately by a qualified marine fitter.

All safety gear should be given a full check and service each year (see 14 tips to make sure your safety gear is in order), with lifejackets examined more frequently for chafe or damaged stitching, and to confirm that the inflation bottle is firmly screwed in place.

Sails and rig

Examine sails for damage to stitching, as well as nicks, chafe and tears in the fabric – when sailing the smallest damage will show clearly against the sun. Pay attention to high load zones, batten pockets and the leech of headsails.

Checking the rig

Check the rig at least once a season.

A full rig check is a sensible precaution at least once a year. A visual check won’t tell you everything – hairline flaws invisible to the naked eye can cause stainless steel to fail – but it’s a good place to start. Check all terminals and fittings for visual condition and security, paying particular attention to spreader roots and rigging attachment points. At the masthead check the halyard sheaves run smoothly and lubricate them sparingly. Also, check that spreader ends and other items that may damage sails are smooth and well protected with tape.

Budgeting for maintenance

Many failures to maintain an older boat adequately stem from a lack of appreciation of the long-term costs involved. It’s fairly straightforward to budget for routine items such as racing sails that must be replaced frequently, but items with a longer lifespan are a different matter and it’s difficult to predict when they will reach the end of their serviceable life. It is, however, prudent to build a contingency fund from which to pay for essential replacements. I use rough estimates of the useful life of key components to budget ‘big ticket’ expenditure on my boats (see table below).

Maintenance tableIn many cases, items will last much longer than this, but others may fail prematurely. In any case, there’s no harm in being pessimistic about the costs – so for my 30ft boat, putting £100-150 a month aside (in addition to annual maintenance costs) covers the bulk of any essential big ticket items in the long term.

Read our best boat fitting out tips for more maintenance advice.