Repair & maintenance guides
Plain-English, step by step, written for owners. Pick your engine to see the guides that apply to it.
313 of 509 guides · page 7 of 14

How to Inspect and Replace Exhaust Shutters and Flapper Valves
The rubber shutters inside a sterndrive's exhaust and the flappers at an inboard's exhaust outlet are one-way valves that keep water from washing back into the engine. Learn where they are, how they fail, how to check them every year, and why riser service is the perfect time to replace them.

How to Inspect and Replace Sacrificial Anodes (Zincs)
Check the anodes on your outboard, sterndrive or inboard running gear, replace them when they are half gone, and choose the right metal for the water you boat in. Fresh anodes are cheap insurance against expensive corrosion damage to your lower unit, drive and prop.

How to Inspect and Replace Spark Plugs
Pull, read and replace the spark plugs on a gas outboard, sterndrive, inboard or PWC. Fresh, correctly gapped plugs help the engine start easily and run smoothly, and the old plugs tell you a lot about the engine's health.

How to Inspect and Replace Your Bow Eye and Transom Eyes
Check the bow eye and transom tie-down eyes for rust, loose nuts and missing backing plates, and replace and reseal them properly, because a failed bow eye can let the boat slide off the trailer.

How to Inspect and Use the Trailer Winch, Strap, Tie-Downs and Safety Chains
Check the winch, strap or cable, bow safety chain, transom tie-downs and the safety chains to your vehicle, and learn how each one is meant to be used. These parts keep the boat on the trailer and the trailer behind your truck.

How to Inspect Boat Trailer Axles, Leaf Springs and Hangers
Check the parts that actually hold your boat off the road: the axle tube, leaf springs, hangers, shackles, bushings and U-bolts (or the rubber torsion axle on newer trailers). Learn what rust-through, broken leaves and worn shackles look like, how uneven tire wear points to a bent axle, and when it's time to replace instead of patch.

How to Inspect Engine Belts and the Tensioner on Sterndrives, Inboards and Diesels
On many inboard, sterndrive and diesel engines, one belt runs the water pump, the alternator and often the power steering. If it breaks or jumps off, the engine overheats and the steering goes heavy at the same moment. Learn how to inspect the belt, tensioner and pulleys, check tension, and carry the right spare.

How to Inspect Wakeboard Tower, T-Top and Bimini Hardware
Towers, T-tops and biminis carry tow ropes, speakers, boards, electronics and wind loads, all on a handful of bolts. Learn how to check the welds, bases, backing plates, bolts, folding hinges and accessory loads before a crack or a loose bolt becomes an accident.

How to Inspect Your Boat's Fuel Tank, Fill, Vent and Hoses
A leaking gas tank is one of the most dangerous problems a boat can have, and it usually starts out of sight. Learn how to inspect portable and built-in tanks, spot aluminum tanks corroding from below, know the ethanol risk for old fiberglass tanks, and check the fill, vent, hoses, clamps and sender, plus why tank replacement is a job for a pro.

How to Inspect, Clean and Replace Vented Loops (Anti-Siphon Valves)
A vented loop is a small, easy-to-forget fitting that stops seawater from siphoning into your engine or through your head and into the boat. Learn where they live, why they must sit well above the waterline, how to clean a sticky or clogged valve, when to replace it, and how to spot the hydrolock damage a failed one can cause.

How to Inspect, Inflate and Replace Boat Trailer Tires
Check your trailer tires the way the pros do: the right type (ST), the right load range, the right cold pressure, and an honest look at their age. Tires are the number one reason boat trailers end up on the side of the highway.

How to Install a Backup Bilge Pump and High-Water Alarm
Add a second, larger automatic bilge pump mounted above the primary, with its own overboard discharge and a loud high-water alarm wired so it works even with the battery switch off, then test it every month so it buys you real time if the boat starts taking on water.

How to Install an Inspection Port (Deck Plate) in a Deck or Bulkhead
Add a screw-out or pry-out deck plate so you can reach hidden nuts, wiring, hoses and through-hulls, or check a deck core for rot. Learn where it is safe to cut, how to pick and size the port, how to seal a cored deck with epoxy, and how to bed the ring so it never leaks.

How to Install EVA Foam Decking (SeaDek-Style Pads) on Your Boat
Closed-cell foam decking makes a hard fiberglass deck grippy and comfortable underfoot. Learn when a peel-and-stick DIY job makes sense, how to template, cut and prep, the temperature and gap rules, how to lay pads without trapped air, and how to clean, repair and eventually remove them.

How to Keep a Boat Maintenance Log and Organize Your Receipts
Set up a simple maintenance log that records the date, engine hours, work done, parts and who did it, and keep receipts and photos organized. Good records help with warranty and insurance claims, show buyers the boat was cared for and reveal wear patterns before something fails.

How to Keep Mice and Rodents Off Your Stored Boat
Mice love a stored boat: dry, quiet and full of soft nesting material and tasty wire insulation. Learn how to remove what attracts them, close their way in, choose deterrents and traps that actually work, avoid the risks of poison, and check the wiring safely in spring.

How to Keep Your Boat in the Water Over Winter (De-Icers, Covers and Checks)
Wintering afloat can be safe if you still winterize every water system, keep the bilge pump and batteries working, use a de-icer correctly on a GFCI-protected circuit, respect the shock and thin-ice risks, and visit the boat regularly.

How to Launch and Retrieve Your Boat Alone
A repeatable routine for putting a trailer boat in and taking it out by yourself: what to do in the staging area, how to rig one long line so you can control the boat from the dock, when power loading is off-limits, and the safety habits that keep you, your boat and the next boater out of trouble.

How to Load Your Boat Safely: Capacity Plate, Balance and Stability
Too much weight, or the right weight in the wrong place, is behind most small-boat capsizes and swampings. Learn to read the capacity plate (persons, weight and horsepower), add up your real load, balance it side to side and fore and aft, and adjust for rough water, water aboard and towing riders.

How to Match Gelcoat Color for Small Repairs
Get a chip or screw-hole repair to blend in with your hull instead of standing out as a bright patch. Learn to polish first so you see the real color, find your builder's color code or a matched gelcoat, tint by tiny steps, test cured samples in daylight, and allow for sun fading.

How to Mount Rod Holders, Fish Finders, Cleats and Antennas Without Causing Leaks
Add accessories to your boat the right way, with through-bolts, backing plates, sealed core and proper wire pass-throughs, so every new hole stays dry and strong. Also learn where you should never drill.

How to Paint a Boat Bilge (Prep, Paint Choice and What to Leave Bare)
A freshly painted bilge is easier to keep clean and makes small fuel, oil, coolant and water leaks easy to spot. Learn how to degrease and sand, pick between alkyd bilge paint and epoxy coatings, ventilate safely, and keep paint off the parts that must stay bare.

How to Prepare for a Free Vessel Safety Check
Volunteers from the Coast Guard Auxiliary and America's Boating Club will inspect your boat's safety gear for free, with no ticket if something is missing. Learn how to request a Vessel Safety Check, what the examiner looks at, how to get your boat ready and what to do with the fix list.

How to Prepare Your Boat for a Hurricane or Tropical Storm
Make a written storm plan before the season, then haul out or secure the boat with doubled lines and chafe gear, strip off everything that catches wind, and check it safely after the storm. Never ride out a hurricane aboard.
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