BoatMend

Repair & maintenance guides

Plain-English, step by step, written for owners. Pick your engine to see the guides that apply to it.

342 of 509 guides · page 11 of 15

SafetyModerate

Lightning and Your Boat: Protection, Storm Safety and After-Strike Inspection

How lightning damages boats, what a professionally installed protection system (ABYC and NFPA 780 guidance) can and cannot do, what to do when a storm catches you on the water, and a step-by-step inspection checklist after a strike, including the haul-out, compass, electronics, through-hulls and the insurance claim.

2 h All engines Shop: $500-5000
TroubleshootingModerateDraft

Losing Coolant With No Visible Leak? How to Pressure Test a Closed Cooling System and Its Cap

When the coolant level keeps dropping and you can't find a drip, a simple hand-pump pressure tester can show where it's going. Learn how to test the system and the pressure cap safely on a cold engine, isolate the heat exchanger and coolant-heated appliances, and recognize the signs of a head gasket or internal leak that need a mechanic.

2 h Marine diesel, Gas inboard, Sterndrive (I/O) Shop: $150-600
TroubleshootingModerate

Low Oil Pressure Warning: What to Do on a Sterndrive, Inboard or Diesel

A low oil pressure alarm or a gauge that drops toward zero means the engine may be running without proper lubrication. Learn what to do in the first minute, the simple checks you can make yourself, how to tell a bad sender from a real pressure problem, and why you should never keep running on the alarm.

1 h Sterndrive (I/O), Gas inboard, Marine diesel Shop: $150-600
ElectricalModerate

Low-Voltage Disconnects: Keep the Stereo and Fridge from Killing Your Battery

A low-voltage disconnect (LVD) automatically cuts non-essential loads like the stereo, fridge and cabin lights before they drain the battery you need to start the engine. Learn how these devices work, which loads belong behind one and which never do, how to pick the cut-off point for lead-acid or lithium, and how to install one safely.

2 h 30 min All engines Shop: $200-500
SafetyEasy

Make a Fire Escape Plan for Your Boat: Exits, Extinguishers, Roles and Shutoffs

Map two ways out of every cabin, put extinguishers where you can actually reach them, assign who does what, and practice shutting off fuel and power and getting everyone off upwind. A boat fire leaves only a few minutes, so the plan has to be made and walked through before you need it.

1 h All engines
ElectricalModerate

Make Your Own Boat Wiring Diagram

Trace your boat's 12-volt circuits one wire at a time, label them so the labels last, and draw a simple diagram you keep aboard. It takes a few weekends, but it turns every future electrical problem or upgrade into a faster, cheaper job.

8 h All engines Shop: $150-600
SafetyEasy

Man-Overboard Recovery Gear: Throwables, Lifesling, Ladders and MOB Alarms

Set up and check the gear that gets a person in the water back aboard - a throwable within reach, a floating rescue line or Lifesling-style sling, a boarding ladder someone in the water can pull down, and MOB alarms or AIS beacons - and practice the drill so it works when it counts.

45 min All engines
Buying & ownershipModerate

Marina and Storage Liens: How Lien Sales Work, Buying a Lien-Sale Boat, and Not Losing Yours

How unpaid slip, storage or repair bills turn into a lien and then a sale, using Florida and California as examples; what an owner can do to stop it; and how a buyer checks that a lien-sale or abandoned boat comes with paperwork the state will actually title. Every state has its own process and deadlines, so confirm with your state agency.

2 h All engines
Buying & ownershipEasy

Marina Slip and Storage Contracts: What to Read Before You Sign

Walk through a slip, mooring or winter storage contract clause by clause: insurance and additional-insured requirements, hold-harmless and waiver-of-subrogation language, liveaboard and work rules, DIY and outside-contractor limits, storms, termination, refunds and lien rights, plus the questions to ask the marina and your insurer. Practical guidance, not legal advice.

1 h All engines
ElectricalEasy

Marine Battery Care: Test, Charge and Store for Winter

Check your boat battery's health, charge it the right way for its type (flooded, AGM or lithium), and store it so it is ready in spring. Most "boat won't start" calls start with a neglected battery.

1 h All engines Shop: $50-150
Routine serviceModerate

Marine Diesel Service: Oil Change, Fuel Filters and Bleeding Air

Change the oil and oil filter, replace the primary and secondary fuel filters, and bleed air from the fuel system on a Yanmar, Volvo Penta, Beta, Cummins or similar marine diesel. These three skills cover most routine diesel care and can get you out of trouble when the engine dies on a passage.

2 h 30 min Marine diesel, Gas inboard Shop: $300-700
Routine serviceModerate

Marine Diesel Turbocharger Care: Warm-Up, Cool-Down and Simple Checks

A turbocharger needs little attention, but the attention it needs matters. Learn how to warm up and cool down a turbo diesel, keep its oil and air clean, track boost, spot leaks and salt corrosion early, and know when a turbo needs a professional.

45 min Marine diesel Shop: $200-3500
TroubleshootingModerate

Marine Diesel Won't Start: Troubleshooting From Battery to Fuel

Work through the usual reasons a Yanmar, Volvo Penta, Westerbeke, Beta or similar marine diesel won't crank, or cranks but won't fire, starting with the free and simple checks. Most no-starts come down to the battery, preheat, air in the fuel or a fuel shutoff solenoid.

1 h Marine diesel, Gas inboard Shop: $150-600
Routine serviceModerate

Marine Generator Routine Maintenance and CO Safety

Keep an Onan, Kohler/Rehlko, Northern Lights, Westerbeke or similar marine generator reliable with regular checks of oil, raw-water cooling, fuel, exhaust and the start battery, plus a monthly run under load. Generator exhaust is a leading source of carbon monoxide on boats, so safety checks come first.

2 h Marine diesel, Gas inboard Shop: $300-800
TroubleshootingModerate

Marine Generator Won't Start or Keeps Shutting Down

A step-by-step troubleshooting guide for a boat generator (genset) that won't crank, cranks but won't start, starts and then dies, or runs without making power. Work from switches, battery and fuel to the safety shutdowns for low oil, high temperature and lost raw-water flow, without flooding the engine or risking carbon monoxide.

1 h Gas inboard, Sterndrive (I/O), Marine diesel Shop: $150-600
Hull & systemsEasy

Marine Head and Holding Tank Care: Odors, Clogs, Pump-Outs and Winterizing

Keep your boat's toilet and holding tank working and odor-free, clear common clogs, pump out the right way, and winterize the system. Also covers the Y-valve and the federal no-discharge rules every owner with a head needs to follow.

1 h All engines Shop: $150-600
Hull & systemsEasy

Marine Sealants Explained: 5200, 4200, 4000UV, Polysulfide, Silicone and Butyl Tape

Pick the right sealant before you bed a cleat, a through-hull, a window or a transducer. The wrong goo either leaks in a year or glues a part on so hard you damage the boat getting it off.

30 min All engines
TroubleshootingModerate

Marine Stereo Troubleshooting: No Power, Lost Settings, No Sound or Bluetooth Trouble

Track down a boat stereo that won't turn on, forgets its presets, resets when the engine cranks, plays no sound or won't keep a Bluetooth connection. Work from the free checks (switches, resets, fuses) to voltage tests, speaker wiring, water damage and software updates before you buy a new unit.

1 h All engines Shop: $100-350
Hull & systemsEasyDraft

Marine Vinyl Stain Removal: Ink, Sunscreen, Grease, Mildew and Pink Stain

A stain-by-stain plan for boat seat vinyl that follows your vinyl maker's own cleaning list, starts with the mildest method, and keeps you away from the products that strip the protective top coat, rot the stitching or crack the vinyl.

1 h All engines Shop: $100-400
Hull & systemsModerate

Marine Water Heater Care: No Hot Water, Relief Valve, Anode and Winter Draining

Most boat water heaters warm up two ways: a 120-volt electric element at the dock and a coil that borrows hot coolant from the engine underway. Learn the safe owner checks when the hot water quits, what a dripping relief valve means, and how to drain and bypass the tank for winter.

1 h All engines Shop: $150-600
TroubleshootingModerate

Milky Engine Oil or Water in the Oil - What It Means and What to Do

Milky, creamy or rising engine oil usually means water is getting into the engine. Learn why you should stop running it right away, how to tell harmless condensation from a real leak, and which parts are the usual suspects: head gaskets, exhaust risers and manifolds, intake manifold gaskets, oil coolers and freeze cracks.

1 h Outboard, Sterndrive (I/O), Gas inboard, Marine diesel
SafetyEasy

Missing or Faded Capacity Plate: How to Read It and Get a Proper Replacement

The capacity plate tells you how many people, how much weight and how much horsepower your boat can safely handle. Learn what each line means, which boats must have one under 33 CFR 183, how to order a replacement from the builder, what to do if the builder is gone, and why homemade numbers are a bad idea.

30 min All engines
Hull & systemsModerate

Mounting Hardware Where You Can't Reach Behind: Blind Fasteners

Learn how to mount light accessories on a boat when you can't get a hand behind the panel, using blind rivets, rivet nuts, well nuts, toggle anchors and bonded studs, when to cut an inspection port instead, and what must never be held by a blind fastener.

1 h 30 min All engines Shop: $100-400
Routine serviceEasy

Moving Your Boat From Fresh to Salt Water (or Back): Anodes, Flushing, Corrosion, Bottom Paint and Trailer Upgrades

What to change when a lake boat moves to the coast, or a saltwater boat moves inland: switching anode material, a flush-after-every-trip routine, raw-water and closed cooling parts that wear faster in salt, bottom paint that suits your hull and drive, marine-grade hardware, and trailer upgrades that survive salt dunks. Built from BoatUS, Mercury, Yamaha and Boating Magazine advice.

3 h Outboard, Sterndrive (I/O), Gas inboard, Marine diesel, Jet ski / PWC Shop: $200-800

Safety: BoatMend is for information only and does not replace a certified marine technician. You are responsible for your safety and your boat. Read the full disclaimer.