BoatMend

Repair & maintenance guides

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

370 of 509 guides · page 8 of 16

Routine serviceModerate

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.

1 h 30 min Sterndrive (I/O), Gas inboard Shop: $150-450
Routine serviceEasy

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.

45 min Outboard, Sterndrive (I/O), Gas inboard, Marine diesel Shop: $100-300
Routine serviceEasy

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.

45 min Outboard, Sterndrive (I/O), Gas inboard, Jet ski / PWC Shop: $100-300
TrailerModerate

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.

2 h All engines Shop: $150-500
TrailerEasy

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.

45 min All engines Shop: $50-200
TrailerModerate

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.

1 h All engines Shop: $150-900
Routine serviceEasy

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.

45 min Sterndrive (I/O), Gas inboard, Marine diesel Shop: $100-300
Hull & systemsEasy

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.

1 h All engines Shop: $100-400
SafetyModerate

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.

1 h 30 min Outboard, Sterndrive (I/O), Gas inboard, Jet boat Shop: $150-400
Hull & systemsModerate

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.

1 h Gas inboard, Marine diesel, Sterndrive (I/O) Shop: $150-400
TrailerEasy

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.

45 min All engines Shop: $40-120
Hull & systemsEasy

How to Install (and Remove) a Keel Guard on a Trailer Boat

An adhesive keel guard protects the bow and keel line of a trailer or beaching boat from sand, rocks and ramps. Learn when it's worth it, how to prep and apply one the way the maker intends, and how to take it off later.

1 h 30 min Outboard, Sterndrive (I/O), Jet boat Shop: $200-500
SafetyModerate

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.

3 h All engines Shop: $400-1000
Hull & systemsModerate

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.

3 h All engines Shop: $200-600
Hull & systemsModerate

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.

4 h All engines Shop: $500-5000
Routine serviceEasy

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.

1 h All engines
SeasonalEasy

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.

1 h 30 min All engines Shop: $150-1500
SeasonalModerate

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.

4 h All engines Shop: $400-2000
TrailerModerate

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.

30 min All engines
SafetyEasy

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.

20 min All engines
Hull & systemsModerateDraft

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.

3 h All engines Shop: $150-500
Hull & systemsModerate

How to Mount or Re-Tighten an Outboard on the Transom

A loose outboard can steer badly, crack the transom or fall off the boat. Learn how to center the motor, check engine height, tighten clamp screws, seal and bolt through the transom with backing plates, add a safety cable on small motors and spot transom flex before it becomes a costly repair.

1 h 30 min Outboard Shop: $150-500
Hull & systemsModerate

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.

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

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.

10 h All engines Shop: $500-2500

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