Repair & maintenance guides
Plain-English, step by step, written for owners. Pick your engine to see the guides that apply to it.
339 of 509 guides · page 11 of 15

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

NMEA 2000 Network Basics and Troubleshooting (Plus Chartplotter Updates)
Understand the backbone, terminators, power tap and drop cables that tie your chartplotter, engine data, GPS, depth and autopilot together, then track down why a device keeps dropping off. Finish by updating chartplotter and device software the safe way.

No Spark - Safe Ignition Checks for Outboards, Sterndrives, Inboards and PWCs
Engine cranks but never fires, and you suspect the ignition? Work from the cheap, common causes (kill switch lanyard, key switch, plug wires and caps, plugs, battery) to a proper spark test, and learn what the stator, CDI and coils do and when it is time for a dealer.

Oil or Fuel in the Bilge: Safe, Legal Cleanup
What to do when you find oil, diesel or gasoline in your bilge. Soak it up with oil-only absorbents, keep it from being pumped overboard, dispose of it properly, report any sheen on the water to the National Response Center, and find the leak so it does not happen again.

On-Water Towing Plans: BoatUS vs. Sea Tow vs. Your Insurance Towing Coverage
Compare a BoatUS or Sea Tow towing membership with the towing coverage on an insurance policy: what each pays for (tows, soft ungroundings, jump-starts, fuel delivery), why hard groundings and sinkings are salvage that only hull insurance covers, how to call for help, and what to have ready when you do.

Onboard Tool Kit and Spare Parts: What to Carry on a Day Boat or a Cruiser
Build a tool kit and spares box that fits your boat and how far you go. A blown fuse, a clogged fuel filter or a dinged prop shouldn't end the day or turn into an expensive tow.

Outboard Fell Overboard or Engine Got Submerged: What to Do in the First Hours
A dunked engine can often be saved, but only if you act fast and in the right order. Learn what to do (and what never to do) in the first hours after an outboard goes overboard or a boat swamps, how to buy time until a shop can take it, and when it is a loss.

Overheat Alarm: What to Do in the First 60 Seconds
A short, practiced routine for the moment the temperature alarm goes off: take the load off, look for cooling water, shut down if it isn't there, and check every space the exhaust runs through for heat or fire. Based on a June 2026 Coast Guard safety alert about a fatal fire that started with an overheat alarm.
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