Boat maintenance is an expansive subject. Boats are complicated, and if you’ve just bought your first boat, there’s a ton of stuff to learn. Maintenance is one of those things. No matter how long you own a boat, you’ll learn something new about maintenance tasks every year that goes by.

No general boat maintenance guide will ever be complete. Why? Because:

  • There are too many different types of vessels, and they each have special needs.
  • Every boat is made up of customized systems, so no two boats are exactly alike.
  • Boating environments are drastically different. A boat sailed year-round in tropical salt water will be maintained differently than a boat used seasonally on a northern lake.
  • Boaters use their vessels differently. A daily workboat will require a different maintenance routine than a weekend sailor. A boat kept in the water will have a different schedule than someone who keeps their boat on a trailer.
  • A boater traveling far from home or into remote areas may maintain their vessel to a different degree than someone who sticks close to home.
  • Boaters have different personal values when it comes to the appearance of their vessels. Some may value ease of use and reduced maintenance, while others may want glossy teak and a shiny hull — shipshape and Bristol fashion.

Let’s try to narrow down the field. The following summary of boat maintenance tips is developed with a liveaboard boat in mind. That means a vessel large enough to have basic accommodations, which is kept in the water at least most of the year. These vessels typically have an inboard boat engine and more complicated systems than trailerable boats.

Boat Maintenance Tips for Boat Owners

A Beginner's Guide to Boat Maintenance_WhereYouMakeIt

First, Create Your Own Boat Maintenance Checklist

When you buy a new-to-you boat, the first step is to sit down and inventory all of the installed equipment. Figure out the make and model of the following items, and then go online and download that product’s owner or service manual.

Note: This is a list of common components that most liveaboard boats have, but some vessels might have more or less. Again, every boat is unique.

  • Engine
  • Transmission
  • Generator
  • Alternator
  • Batteries and battery switch
  • Battery charger
  • Water pump
  • Bilge pump
  • Toilet
  • Refrigerator
  • Stove/oven/microwave
  • Air conditioner
  • GPS/Chartplotter
  • VHF radio
  • Autopilot
  • Instruments (depth, wind, speed)
  • Anchor
  • Anchor windlass
  • Dinghy/tender outboard motor

Once you have the manual in hand, you can flip through it and see what it says about installation and maintenance. If you didn’t install it yourself, double-check that it was done correctly. If it wasn’t, fixing it might mean less maintenance or repairs in the future.  Only the big, moving items will have published maintenance schedules. Every engine will have a detailed list. Moving parts like windlasses, winches, and perhaps autopilot drives may have some cleaning or lubrication requirements.

Take all of the data, and make yourself one master spreadsheet. List the tasks you should do monthly, seasonally, or annually. Once you’ve done that, you can start learning how to do the work or finding people who will know how to do it for you.

Gel Coat/Fiberglass Boat Care

There are a few things that simply won’t have an owner’s manual. One of those is the boat itself. Modern boats are almost universally made of fiberglass. This material is a type of robust plastic. It is coated in a thick resin known as gel coat to protect it from UV damage. Gel coat finish is like paint in some ways, but maintaining it requires some specially know-how.

The most beneficial thing you can do to maintain your gel coat is to keep it washed, waxed, and buffed to a shine. Washing your boat with a long handled brush, soft bristle brush, lots of fresh water, and mild soap will remove salt residue and salt crystals. The wax will keep dirt and grime out. The problem with the gel coat is that it is actually porous. Once it loses its protective wax, it absorbs dirt, water, grime, and even stains. If left in a damp environment, mold and mildew can start growing inside of the gel coat. That is very hard to clean up, so it’s much better to prevent it from happening.

It is possible to bring an old dull gel coat back to a shine by compounding it. Compound is like wax, only it contains grit that removes oxidization and restores the shine. Compounding is then followed up with a thick application of standard wax. There are countless miracle cures and snake oils on the market to help you fix gel coat problems. You can spend a lot of money, but you can address most problems with high-quality compound, wax, and a stain remover. The best stain removers for fiberglass contain oxalic acid, although simple lemon juice works pretty well too.

Avoid using harsh chemicals on your boat when it is in the water since they will inevitably wash off into the water. You should always avoid bleach. You can do general cleaning with fresh water and an environmentally-friendly biodegradable boat soap available at any marine store.

Exterior Brightwork

Boat owners have a love/hate relationship with woodwork. Some owners value the classic look that teak gives a boat, and others would rather paint it over to avoid the work. If you look at new production boats, it’s rare to see any exterior brightwork as the later viewpoint has become more common. In truth, keeping exterior teak is an extra chore, but not an onerous one. Teak is a durable tropical hardwood, and when cared for properly, it can last decades.

You can keep raw teak clean with simple washings. Between washing, you may choose to use a teak cleaner, usually made with oxalic acid. There are many oils and protectants you can apply to help keep it clean. Left untreated, teak turns a lovely ash grey color. An extra step can be taken to add a layer of shine to the wood. This is commonly called varnishing, but there are actually many products that you can use to achieve the look. Varnish is the traditional method, but it’s a lot of work. There are other modern two-part clear coatings and easy-to-apply alternatives like Cetol that can look great and require much less work.

The key to all of these coatings is to realize that they cannot last forever. The sun will deteriorate them, and most will only last a year or so. Once the coating has begun to chip and flake off, the entire piece of teak must be stripped down bare, cleaned, and recoated. That’s a major project. The solution is to have a schedule of regular maintenance rather than repair. Every six months, you should clean the teak and apply a new top-coat of product. An easy chore every six months prevents a difficult project every year. A penny saved is a dollar earned, so to speak.

Once the wood is protected, wash it regularly with regular boat soap.

Canvas

Boat canvas is made of strong UV-resistant fabrics like the Sunbrella brand. These are treated to be waterproof, and if kept up, they can last years. But all exterior canvas on a boat is a disposable item that will need to be replaced every decade or so.

You can keep canvas looking new by washing it regularly with boat soap. If your canvas no longer beads water, you can treat it with a waterproofing chemical like 303. A canvas shop can usually restitch panels when the seams begin to part. It is usually the thread that deteriorates first. Once the fibers of the fabric begin to deteriorate, the panels will need to be replaced.

Stainless Steel Fixtures and Metal Components

Most metal that you see on boats is stainless steel or aluminum. Regular steel and many other metals will quickly rust or corrode when exposed to salt air, much less salt water. As long as stainless has a shiny finish, it should wash off with regular boat soap and be fine. If it loses its luster, it will need to be polished and protected.

Interior Wood Finishes

Interior woodwork also needs to be cared for, but it will generally last decades since it is protected from the sun. Raw wood is commonly cleaned and treated with a simple oil, like lemon oil. Interior coatings range from traditional varnish to hard coatings like two-part polyurethane or lacquer. Interior cleaning isn’t unlike a house. You may choose to vacuum, sweep, or use a damp cloth.

Engines and Daily Basic Boat Maintenance Checklist

All engines have lubrication requirements that should be met. Every engine has an owner’s manual and a maintenance manual laying out how to accomplish them. The list will be a little different depending on whether you have a gas or diesel engine.

Proper engine maintenance starts every time you use the boat. The manual should lay out your daily checks, and your engine checklist will usually include the following.

  • Checking the engine oil level
  • Checking the coolant level
  • Checking the fuel filter bowl
  • Checking the gear case fluid level
  • Checking the belt tension
  • Inspecting electrical lines
  • Inspecting the general condition of the motor, especially for any oil leaks into the bilge or other suspicious signs of trouble.

Doing these tasks before every day’s adventure goes a long way. It’s a lot like medicine—finding trouble early heads of bigger problems later and saves you money in the long run. Once you’ve done these tasks a few times, you can knock them out in a few minutes.

During your daily checks, you can also notice changes as they happen. Is the oil level going down? What if the oil has turned cloudy or milky? Did the engine seem to take longer to start than it normally does? Is the transmission making an extra clicking noise? Does it burn extra fuel all of a sudden? Little things like this aren’t going to be noticed by a mechanic that comes once a year, so it’s up to you.

The owner’s manual will lay out what other maintenance is required. Oil changes and a new oil filter are typically done every 100 hours or six months. Annual servicing usually includes spark plugs for gas motors, coolant flushes, anodes, fuel filter changes, and belt adjustments. The paint on your engine helps prevent corrosion. Most engines have steel components, which will rust if exposed to salt water. If you notice chipped paint or corrosion popping up on your engine, tend to it immediately with a wire brush and some fresh paint.

These recommendations cover any engine, even those to run electrical generators.

Boat Bottoms

A Beginner's Guide to Boat Maintenance_WhereYouMakeIt

There’s one task that has no land equivalent—the bottom. Boats that stay in the water for any length of time attract all sorts of sea critters looking for a home. Barnacles are the prime example. They form hard shells that foul the water flow over the bottom and reduce your speed. All sorts of worms, clams, plants, and algae will grow on an unattended boat bottom also.

In extreme cases, a dirty hull can be so severe that the engine will overheat when you try to go somewhere. Not only does the dirty hull require more work to push through the water, but the water intake hole for the engine can become plugged. Even moderately dirty bottoms will increase your fuel costs.

To prevent growth, boaters paint the underside of the boat with toxic paint. The most effective paints contain copper. In the old days, tall ships were plated with copper panels to prevent growth. Besides the growth, the paint on the bottom is usually applied on top of a barrier coat. The barrier coat is a hard surface that water cannot penetrate. Since gel coat is porous, it’s not the best surface to use underwater. Over time, water can enter the gel coat and fiberglass and cause osmotic blistering which requires expensive and time-consuming repairs.

No matter how good your bottom paint is, all boats need an occasional scrub. The more a boat moves, the fewer scrubs it needs. Liveaboard boats that seldom leave the dock need scrubbing more often than cruising boats that travel hundreds of miles a month.

In most areas, boat owners hire the local diver to do regular cleanings. They usually come once a month and charge between $3 and $5 per foot. Divers also help you out by inspecting everything, letting you know if you have a fishing line wrapped on your propeller shaft or a loose propeller nut.

If you’re a diver or a strong freediver, you can clean your own bottom. Use a wide plastic putty knife to scrape stuff off gently, and then buff it clean with a Scotchbrite pad. Pay particular attention to the prop and running gear, which usually foul before everything else.

Boats also need their underwater anodes inspected and replaced regularly. These are sacrificial metal tabs bolted to the prop shaft and hull (although some boats might have more). They prevent damage to other parts of the boat by decaying slowly. The science behind them is beyond the scope of this article, but they should be replaced every six months at least. A diver can do it in the water, or you can do it during a haul out.

Haul Outs

In some areas where the boating season is short, boats are regularly hauled out for the off-season. This is a cheap and safe way to store them over winter, limiting their overall lifetime saltwater exposure.

Most bottom paints last no more than two years, which means the boat will need to be hauled out and repainted about that often. At the same time, it’s easy to do any work to the prop, shaft, rudders, anodes, or through-hulls that needs to be done.

If the work is a simple new coat of paint and the yard allows it, it’s fairly straightforward to apply another coat of bottom paint. The type you use must match the type already on the boat, though, so research carefully.

Remember that bottom paint is extremely toxic. So never sand, scrape, or paint it without taking precautions. When in doubt, have the yard do bottom paint projects for you.

Through-hulls

Plumbing on boats is a complicated matter, but most large vessels have several pick-ups and drain below the waterline. The opening in the hull that allows the water to pass is called a through-hull, and the valve attached to it that can shut it off is called a seacock.

Any opening in the hull below the waterline should be paid extra attention to. Go around once a month and “exercise” the valves by opening and closing them. Lubricate them annually. Never force a valve—if it’s stuck, leave it stuck until your next haul out.

While you’re at it, make sure all of the hoses and hose clamps on those valves are in good condition and secure. Hoses below the waterline should use two hose clamps for extra security.

The general condition of the valve and through-hull is important, too. They should always be made of marine-grade bronze. Never use hardware store parts that use brass, which will decay quickly in the marine environment. If you see discoloration or corrosion on a through-hull, address it quickly.

A broken or damaged through-hull can sink a boat. They’re impossible to work on or replace with the boat in the water. When the boat is hauled out, make sure the through-hulls are sound and replace any that are suspect. Make sure they’re in good condition before every launch.

Winterization

If you are in an area where freezing weather is expected, it can wreck your boat’s systems. Anything that has water in it can potentially freeze. When water freezes, it expands. So if that water is inside a pipe or hose, it can easily crack the hose.

Every year, boats sink because their owners did not properly winterize them. If a hose connected to a through-hull bursts, it will start leaking, and the boat might sink. Water left in the engine’s cooling system can cause expensive and catastrophic damage to the engine. It’s a costly mistake, but it’s also easily avoidable.

All systems are winterized differently, but anything that has water must be attended to. All through-hulls and seacocks, the engine, the toilet, and the refrigerator or air conditioning must be either drained completely or treated with an environmentally friendly antifreeze.

General Boat Maintenance FAQs

A Beginner's Guide to Boat Maintenance_WhereYouMakeIt

Are Boats High Maintenance?

Boats have many systems that make them run, from their engines to underwater plumbing and electrical. In addition, liveaboard boats often have refrigeration and air conditioning systems. All of these systems are exposed to some of the most damaging and corrosive environments imaginable—doused with seawater, constantly vibrating and moving, and left outside in the sun’s damaging UV rays.

In short, yes, boats are high maintenance.

How Much Does it Cost to Maintain a Boat?

Estimating costs is nearly impossible, but over the years, some good tidbits of advice have surfaced. One commonly quoted estimate is that annual boat maintenance is usually about one-tenth the purchase price of the boat.

By that estimate, a $5,000 vessel would take about $500 per year to maintain, and a $300,000 boat would need about $30,000. That’s a dramatic difference, but the person who spent $300,000 on a boat is far more likely to hire professionals. So as radical as it seems, it usually holds true.

Another common piece of advice is to only spend half of the money you can afford to on the boat’s purchase. Then, you’ll have half left over for maintenance, repairs, upgrades, and enjoyment.

Won’t a New Boat Require Less Maintenance?

Older boats will, of course, require more upkeep than new ones. But the annual costs of keeping a vessel in seaworthy condition don’t actually vary as much as you might think. Maintenance like oil changes, washes, and waxes remain constant. Most boaters will tell you that new boats require just as much equipment, repairs, and maintenance as an older one does.

Can You Save Money By Doing Maintenance Yourself?

The costs to maintain your boat will vary based on several factors, including the task at hand and whether or not you’re open to doing your own work.  A common task is waxing the hull. Fiberglass requires seasonal applications of wax to maintain the outer gel coat. The less it has been waxed, the quicker the gel coat will deteriorate. At some point, the boat will have to be painted.

A few bottles of wax and an electric buffer will cost less than $250. Then, it’s up to you to wash the boat and carefully compound and wax it. How much you want it to shine is up to you and how much time you put into it. The buffer, of course, will last you more than one application. If, on the other hand, you wanted to have the work done by a professional boat detailer, you will be paying by the hour or by the foot. Many boat jobs are billed by the length of the boat. If compounding and waxing cost $25 per foot on a 40-foot boat, the total will be about $1,000.

The math is clear and simple—there’s much less cost out of pocket if you do it yourself. But this only works if you aren’t paying yourself and have nothing else you should be doing with your time. Before you go diving into a boat project, you’ve got to ask yourself, “How much is my time worth?”

A moderate-sized liveaboard vessel can easily take three or four days to compound and wax. It’s not a fun job, even in the best conditions. Add a sunburn and hot summer afternoon, and it’s downright miserable. Never underestimate the true costs of the DIY project!

How Often Should a Boat be Serviced?

Most tasks you need to complete will be every 100 operating hours or every six or twelve months. This includes engine, fiberglass, and boat systems chores. For the exact number, you should look in the owner’s or operator’s manual for each item in question.

Conclusion

Boat maintenance is a broad topic, and there are certainly plenty of expensive and complex items involved. The biggest thing every boat owner has to overcome is their learning curve. Even seasoned boaters experience this problem when they purchase a new-to-them boat—everything requires research, and you’re always learning.

Whether you want to DIY or hire professionals, every owner needs to be in charge of their own maintenance schedules. Know what needs to be done, when, and who is going to do it. Just like shiny teak brightwork, the chore isn’t as onerous as it seems if you stick to the schedule.