BoatMend

Repair & maintenance guides

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

385 of 509 guides · page 10 of 17

Hull & systemsAdvancedDraft

How to Repair or Repaint Worn and Cracked Non-Skid Decks

Bring back grip where the molded non-skid is chipped, cracked, patched or worn smooth. Choose between a molded patch that copies the original pattern, non-skid paint with grit, or textured gelcoat, fix the cracks and soft spots underneath first, and mask for clean, safe edges.

8 h All engines Shop: $300-3000
Hull & systemsModerate

How to Repair or Replace Your Boat's Rub Rail

Replace a torn rub rail insert or the whole rail, reseal the hull-to-deck joint and its fasteners while the rail is off, and stop the deck-joint leaks that often hide behind a worn rail.

8 h All engines Shop: $800-3000
Hull & systemsModerate

How to Repair Small Gelcoat Chips and Scratches

Fill and blend small chips, dings and scratches in your boat's gelcoat with a repair kit so they stop letting water into the fiberglass and look close to new. Also learn to spot damage that is structural and needs a pro.

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

How to Repair Torn-Out Canvas Snaps, Fasteners and Zippers

Fix snaps that have pulled out of your bimini, cover or enclosure, reinforce the torn fabric, choose the right snap metal and setting tool, free stuck snaps, replace Lift-the-Dot and twist fasteners, and swap a worn zipper slider.

1 h All engines Shop: $40-200
Routine serviceEasy

How to Replace a Fuel/Water Separating Filter (and Check for Water in Your Fuel)

Swap the spin-on fuel/water separator on your gas boat and learn to spot water and ethanol phase separation before it stalls the engine. It is one of the cheapest jobs on the boat and one of the best protections for a fuel-injected engine.

30 min Outboard, Sterndrive (I/O), Gas inboard Shop: $75-150
Routine serviceEasy

How to Replace an Outboard Fuel Line and Primer Bulb

A cracked hose or a stiff primer bulb can leak gasoline, starve your engine or shed rubber into the fuel. Learn how to choose Coast Guard-rated fuel hose, the right connectors for your engine brand and good stainless clamps, install the bulb pointing the right way, leak-test the job and get rid of the old parts safely.

45 min Outboard Shop: $100-250
ElectricalModerate

How to Replace Boat Battery Cables the Right Way

Swap corroded, cracked or undersized battery cables for tinned marine cable sized from a chart for its real length and load, with crimped lugs, adhesive heat shrink, terminal boots, solid support and a fuse close to the battery.

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

How to Replace Gas Struts on Boat Hatches, Seats and Consoles

Measure, buy and fit the right gas struts (lift supports) so hatches, seat lids and console doors stay open safely instead of dropping on your head or fingers.

45 min All engines Shop: $100-300
ElectricalModerate

How to Replace Marine Speakers (Including Tower Speakers)

Pick replacement speakers that fit the cutout, match your stereo or amplifier's power and impedance, survive sun and spray, and don't throw off your compass. Then wire them with the right polarity and seal them so water can't reach the back.

2 h All engines Shop: $150-400
Hull & systemsModerate

How to Replace or Re-Cover a Bimini Top

Decide whether you need new canvas or a whole new top, measure your frame the right way, pick a fabric that will last in the sun, check the frame and hardware, and swap the canvas yourself or brief a canvas shop.

3 h All engines Shop: $300-1500
Routine serviceAdvanced

How to Replace the Water Pump Impeller

Replace the rubber impeller that pumps cooling water through your engine, the part most often behind overheating. On many outboards it is a two-hour driveway job that saves a shop bill of several hundred dollars and prevents far costlier heat damage.

2 h 30 min Outboard, Sterndrive (I/O), Gas inboard Shop: $250-650
ElectricalModerate

How to Run New Wires Through a Boat (Chase Tubes, Pull Lines and Deck Penetrations)

Get a new transducer cable, light or power wire from the stern to the helm or up through the deck without a fight: use the chase tube and a fish tape or pull string, protect the wire from chafe and heat, support it every 18 inches, seal every penetration and label both ends.

3 h All engines Shop: $150-600
Routine serviceEasy

How to Sea Trial Your Boat After Maintenance or Repair

A step-by-step test run after service work: dock checks first (leaks, fluids, steering, kill switch), then a gradual climb through the RPM range while you watch temperature and pressure, a wide-open-throttle check against your engine's spec, shifting and trim tests, and a bilge check afterward. Catch a loose clamp or a missed step at the dock, not miles out.

1 h Outboard, Sterndrive (I/O), Gas inboard, Marine diesel, Jet ski / PWC
ElectricalModerate

How to Size a House Battery Bank: Load List, Usable Capacity and Charging

Work out how many amp-hours your boat really uses in a day, how much of a battery's rated capacity you can actually use with lead-acid, AGM or lithium, how much reserve to add, and how your charging sources change the answer, so you buy the right house bank the first time.

2 h All engines
Rules & seamanshipEasy

How to Size, Rig and Inspect Dock Lines and Fenders

Pick the right dock line diameter and fender size for your boat, set up bow, stern and spring lines in a slip, add chafe gear, inspect for wear and UV damage, and double everything up before a storm.

1 h All engines
Routine serviceEasy

How to Synchronize Twin Engines (RPM and Trim)

Twin engines running at slightly different RPM cause a pulsing drone, extra vibration, uneven wear and wasted fuel. Learn how to sync them by tach, sync gauge or ear, use the one-button sync on digital controls, check that your tachs tell the truth, match trim, and know when uneven engines or cable adjustment are a dealer job.

45 min Outboard, Sterndrive (I/O), Gas inboard, Marine diesel Shop: $150-400
Hull & systemsEasy

How to Test and Clean Your Bilge Pump and Float Switch

Make sure your bilge pump actually moves water overboard, both on the manual switch and automatically through the float switch. A working bilge pump is one of the most important safety systems on any boat that stays in the water.

45 min All engines Shop: $100-250
ElectricalEasy

How to Test and Fix Your Boat's Navigation Lights

Learn which navigation lights your boat must show and when, then test them and fix the usual culprits such as corroded sockets, loose pole-light plugs and blown bulbs. Working lights are legally required at night and in poor visibility and are how other boats see which way you are heading.

1 h All engines Shop: $100-300
Routine serviceModerate

How to Test and Replace the Engine Thermostat

Find, test and replace the thermostat that controls your engine's operating temperature. A stuck thermostat can make an engine overheat or run too cold. On most outboards and many sterndrives it is a one-hour job with basic tools.

1 h 15 min Outboard, Sterndrive (I/O), Gas inboard Shop: $150-400
Hull & systemsEasy

How to Touch Up Paint and Corrosion on an Outboard or Sterndrive

Bare aluminum on a lower unit or sterndrive corrodes fast, especially in salt water. Learn how to find the cause, clean off corrosion, prime and repaint with the right products, and what must never be painted, such as anodes and sensors.

2 h Outboard, Sterndrive (I/O) Shop: $150-500
ElectricalModerate

How to Troubleshoot Dash Gauges, a Dead Tachometer or a Wrong Fuel Gauge

Work through dead or wrong dash gauges from the cheapest check to the most involved: fuses and breakers, power and ground, the gauge-versus-sender test, the tachometer's pulse setting and the extra checks for digital network gauges. Most gauge problems turn out to be a bad connection, not a bad gauge.

1 h Outboard, Sterndrive (I/O), Gas inboard, Marine diesel Shop: $150-450
ElectricalModerate

How to Upgrade Your Boat's Lighting to LED (and Keep Your Nav Lights Legal)

Switch cabin, cockpit and courtesy lights to LED to cut battery drain and bulb changes, choose navigation lights that are actually USCG-certified (not just LED bulbs), check voltage range and dimmers, seal every connection, and run the Coast Guard's simple VHF test to make sure the new lights aren't deafening your radio or AIS.

3 h All engines Shop: $200-800
ElectricalModerate

How to Use a 1-2-Both Battery Switch and Run Two Batteries

Learn what the 1, 2, Both and Off positions really do, a simple routine that keeps one battery ready to start the engine, how to check that both batteries are charging, and when an automatic charging relay makes life easier. Rewiring high-current cables is a job for a marine electrician.

45 min Outboard, Sterndrive (I/O), Gas inboard, Marine diesel Shop: $250-800
Hull & systemsEasy

How to Use a Pump-Out Station: Finding One, Hooking Up and Rinsing the Tank

Find a pump-out near you with state maps and free apps, hook up to the deck fitting without spills, rinse the holding tank, leave the station clean for the next boat and know the rules for no-discharge zones and mobile pump-out boats.

20 min All engines Shop: $0-25

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