BoatMend

Repair & maintenance guides

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

299 of 509 guides · page 9 of 13

ElectricalModerate

How to Wire a Marine Stereo, Speakers and Amplifier Safely

Install or fix a boat stereo the way that keeps it working and keeps your battery alive: marine-rated gear, a fused feed from the panel, a solid ground, a plan for the always-on memory wire, UV-proof speakers, and an amplifier fused right at the battery. Plus how to stop the stereo from messing with your VHF and compass.

4 h All engines Shop: $200-800
TroubleshootingEasy

How Water Gets Into Boat Fuel (and How to Stop It)

Water in the fuel is one of the top causes of rough running and dead engines, and it almost always has an entry point you can find. Work from the jar test through the fill cap O-ring, a recessed deck fill, the tank vent, the sending unit gasket and your washdown habits, and learn how much condensation really matters.

1 h Outboard, Sterndrive (I/O), Gas inboard, Marine diesel Shop: $100-400
Hull & systemsModerate

Hull Blisters (Osmosis): How to Tell Cosmetic Pimples From Serious Pox

Learn what osmotic blisters are, how to inspect a fiberglass bottom at haul-out, which blisters you can fix yourself with epoxy, what moisture meter readings can and can't tell you, and when to hire an independent surveyor.

4 h All engines Shop: $400-2000
Hull & systemsModerate

Hull Potential Survey: Checking Corrosion Protection with a Reference Electrode

A silver/silver-chloride reference electrode and an ordinary multimeter show whether your underwater metals are really protected by their anodes, whether every fitting is bonded, and whether shore power or the slip is upsetting things. Learn how to take the readings, what under- and over-protection mean in plain terms, and when to call a marine electrician or corrosion specialist.

1 h Gas inboard, Sterndrive (I/O), Outboard, Marine diesel Shop: $150-500
Hull & systemsModerate

Inboard and Sterndrive Engine Mounts: Signs of Failure and How to Inspect Them

The rubber mounts under an inboard or sterndrive engine soak up vibration and hold the engine in line with the drive. Learn the warning signs of a failing mount, how to inspect all of them in under an hour, and why a mount replacement always ends with an alignment check.

1 h Gas inboard, Sterndrive (I/O), Marine diesel Shop: $400-2500
Hull & systemsEasy

Inflatable Boat and Dinghy Care: Cleaning, UV Protection, Leaks and Storage

Keep your inflatable or RIB tender holding air for years. Rinse and clean it the right way, protect the tubes from sun, check pressure with a gauge, find slow leaks with soapy water, service the valves, patch small holes with the correct glue for PVC or Hypalon, and store it clean and dry.

1 h 30 min All engines Shop: $75-300
SafetyEasy

Inflatable Life Jacket Care: Inspect, Test and Rearm

An inflatable life jacket only saves a life if the cylinder is full, the inflator is armed and the bladder holds air. Learn the quick check before every trip, the overnight leak test, how to read replacement dates and how to rearm it after it fires.

30 min All engines Shop: $40-100
Buying & ownershipModerateDraft

Inheriting a Boat: Title Transfer, Coast Guard Documentation, Insurance, Taxes and Keep-or-Sell

What to do when a boat comes to you from a relative's estate: secure it and keep it insured, find out how ownership passes (joint owner, transfer-on-death, probate or a small-estate affidavit), transfer a state title or a Coast Guard documented vessel, deal with the trailer, liens and taxes, and decide whether to keep or sell. General information, not legal or tax advice.

4 h All engines
ElectricalAdvanced

Installing a DC-to-DC Charger: Charging a Lithium or Second Battery Bank from Your Engine

A DC-to-DC charger lets the engine's alternator refill a lithium (or separate) house bank with the right charge profile while protecting the starting battery and the alternator. Learn why you need one, where it can and can't be mounted, how the fusing and cable sizing work, and which settings matter, so you can plan the job or check a technician's work.

6 h Outboard, Sterndrive (I/O), Gas inboard, Marine diesel Shop: $400-1500
ElectricalModerateDraft

Internet Near Shore: Cellular Routers, Signal Boosters and Marina Wi-Fi Extenders

For boats that stay within sight of land, a cellular router, a legal signal booster or a marina Wi-Fi extender can be a cheaper alternative to satellite. Learn which one fits how you boat, why antenna placement and cable length matter, the FCC rules for boosters, how much power they use and how to test that it actually works.

2 h All engines Shop: $300-1500
ElectricalModerate

Is My Engine Charging the Battery? Test the Charging System With a Multimeter

A step-by-step way to find out whether your outboard's stator and rectifier/regulator or your inboard's alternator is really charging the battery, what the voltage readings usually mean, and when the problem is just a dirty connection. Exact test specs come from your engine's service manual.

1 h Outboard, Sterndrive (I/O), Gas inboard, Marine diesel Shop: $150-900
TrailerEasy

Is My Vehicle Rated to Tow This Boat? Towing Capacity, GCWR and Tongue Weight Explained

The towing number in the ad is only one of several limits. Learn which ratings matter (towing capacity, GCWR, GVWR, axle and tongue limits, hitch class and ball rating), how to weigh your real rig at a truck scale, and when you need trailer brakes and towing mirrors.

1 h 30 min All engines
ElectricalEasy

Isolation Transformer vs. Galvanic Isolator: Which Does Your Boat Need?

Understand how a galvanic isolator and an isolation transformer each protect a boat on shore power, when the heavier, pricier transformer is worth it (stray-current marinas, aluminum boats, liveaboards), and what to ask the ABYC-certified electrician who installs it.

45 min All engines Shop: $200-4000
ElectricalEasyDraft

Keeping Chartplotter Charts and Software Current (Garmin, Raymarine, Simrad, Lowrance, Navionics, NOAA)

Old charts can show buoys that moved and shoals that grew. Learn how chart subscriptions and updates work across the big brands, where NOAA's free charts fit in, how to handle SD cards safely, how to back up your waypoints and routes before anything goes wrong, and a simple yearly routine.

1 h All engines Shop: $0-250
Rules & seamanshipEasy

Lake Engine Restrictions: Two-Stroke Bans, Horsepower Limits, Electric-Only and No-Wake Lakes

Some lakes ban older two-stroke outboards, cap horsepower, allow only electric motors, or make the whole lake no-wake. Learn the common types of rules (with dated real examples like Lake Tahoe and Ohio's lake list), how to tell what kind of engine you have, and how to check before you tow the boat three hours to a ramp you can't use.

30 min All engines
SafetyEasy

Launch Day and Haul-Out Checklist for Trailer Boats

A step-by-step checklist for getting your boat off the trailer and back on again safely and quickly, from the drain plug and tie-downs to the blower and ramp etiquette. Following it in order prevents the classic mistakes that sink boats and back up the ramp.

45 min All engines
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

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.