Repair & maintenance guides
Plain-English, step by step, written for owners. Pick your engine to see the guides that apply to it.
378 of 509 guides · page 11 of 16

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.

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.

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.

Hydraulic Steering: Check Fluid, Bleed Air and Fix Stiff or Loose Steering
Check the fluid in your hydraulic steering helm, bleed out the air that makes steering spongy, and track down the usual causes of stiff, loose or noisy steering. Includes notes for boats with mechanical cable steering.

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.

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.

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.

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.

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.

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.

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.

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.

Jet Outboard Care: Grease, Intake Grate, Impeller Clearance and Shallow-River Habits
A jet outboard trades the propeller and gearcase for a pump, so it needs different care. Learn how mounting height works, why the pump bearing needs frequent grease, how gravel and a worn impeller steal thrust, how to clear the intake safely, and when an adjustment is a shop job.

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.

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.

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.

Life Raft Care: Service Intervals, Hydrostatic Releases, Mounting and the Grab Bag
A life raft you can't launch or that won't inflate is worse than none, because it gives false confidence. Learn how often rafts need professional service, how to pick a service station, when to replace the hydrostatic release, where to mount a canister or stow a valise, the checks you can do yourself, and what belongs in the grab bag instead of the raft.

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.

Livewell, Baitwell and Washdown Pumps - Clean, Troubleshoot and Winterize
Find out why a livewell or washdown pump runs but moves no water, from a closed valve or clogged pickup to an airlock, then clean the system and winterize both sides of every pump so nothing cracks over the winter.

Loss of Power, Hesitation or Misfire - Troubleshooting Guide
Figure out why your engine bogs down, stumbles, will not reach full rpm or runs rough. Work from simple checks like trim, prop and fuel filter to ignition and engine protection modes before paying for diagnostics.

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.
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