BoatMend

Maintenance schedule by engine

The typical intervals BoatMend starts from, with the guide for each job. Your owner's manual always wins: inside BoatMend you can adjust any interval to match it, and reminders follow your engine hours.

120 tasks for gas inboard boats

By engine hours or calendar

Due at whichever comes first.

  • Change engine oil and filter

    Every 75 h or every year, whichever comes first
    4-strokeFirst service at 20 h

    Indmar's maintenance chart: first change at 10-20 hours, then every 75 hours (every 25 hours in severe use), and at least yearly before storage. PCM and MerCruiser inboards typically use 100 hours or yearly. Typical; confirm in your owner's manual.

    How to Use an Oil Extractor Pump for Boat Oil Changes
  • Inspect zinc anodes (engine, shaft, rudder, trim tabs)

    Every 75 h or every year, whichever comes first

    Indmar chart: inspect zinc anodes every 75 hours. Replace at about half worn. Typical; confirm in your owner's manual.

    How to Inspect and Replace Sacrificial Anodes (Zincs)
  • Inspect belts and clean flame arrestor

    Every 100 h or every year, whichever comes first
    4-stroke

    Indmar chart: inspect belts at the first 10-20 hours, then every 100 hours and yearly; clean or replace the flame arrestor every 100 hours and yearly. Never run a gas inboard without its flame arrestor. Typical; confirm in your owner's manual.

    How to Inspect and Clean a Backfire Flame Arrestor
  • Change transmission and V-drive fluid

    Every 300 h or every year, whichever comes first
    First service at 20 h

    Indmar chart: ZF transmission fluid and V-drive fluid at the first 10-20 hours, then every 300 hours or yearly. Use the exact fluid your transmission plate specifies. Typical; confirm in your owner's manual. Boating Magazine (with ZF Marine): look at the old fluid as it drains; ATF should be translucent reddish-pink and oil maple-syrup colored, with no milkiness, grit or burnt smell (if you see any, call a pro); replace the transmission oil cooler's zinc annually. MasterCraft treats shaft coupling alignment as a dealer job in the annual service.

    V-Drive Transmission Care for Wake and Ski Boats: Fluid, Cooler, Coupler and Shaft Seal
  • Check engine-to-shaft alignment

    Every 300 h or every year, whichever comes first
    First service at 20 h Pro recommended

    Indmar chart: check at the first 10-20 hours and yearly. Misalignment causes vibration and wears the cutless bearing and transmission seal. Usually a dealer job.

    Engine Alignment on Sterndrives and Inboards: What to Check and When
  • Replace fuel filter

    Every 300 h or every year, whichever comes first

    Indmar chart: every 300 hours or yearly; Indmar marks it as best done by a dealer on its EFI engines. Boat-mounted water separators are often changed every year. Typical; confirm in your owner's manual.

    How to Replace a Fuel/Water Separating Filter (and Check for Water in Your Fuel)
  • Replace raw water pump impeller

    Every 300 h or every year, whichever comes first

    Indmar chart: inspect every 100 hours, replace every 300 hours or yearly. Keep a spare impeller on board. Typical; confirm in your owner's manual.

    How to Replace the Water Pump Impeller
  • Replace spark plugs and inspect plug wires

    Every 300 h or every year, whichever comes first
    4-stroke

    Indmar chart: every 300 hours or yearly (marked as best done by a dealer). Mercury lists 300 hours or 3 years for MerCruiser. Typical; confirm in your owner's manual.

    Ignition Tune-Up on an Older Sterndrive or Inboard V6/V8
  • Fire extinguisher quick check: gauge, pin, nozzle, date

    Every 1 months

    Five-minute look at every extinguisher: gauge in the operable (green) range, locking pin and seal in place, nozzle clear, no heavy corrosion or damage, and a disposable unit no more than 12 years past its manufacture date. The USCG sets no check frequency for recreational boats; monthly is the NFPA 10 interval that federal rules apply to boats carrying paying passengers (46 CFR 25.30), and a good habit for everyone. Rechargeable units also need annual service by a certified technician.

    How to Check, Mount and Replace Boat Fire Extinguishers
  • Hull protection: re-wax, or check ceramic-coating water beading and apply the maker's topper

    Every 2 months

    BoatUS (2024): wax keeps oxidation away only if you re-wax about every six to eight weeks; a ceramic coating lasts longer but still needs regular washing and, every few months depending on product and climate, a spray-on aftercare layer. Follow your product's instructions. Interval is typical; adjust for sun, salt and storage.

    Ceramic and Polymer Coatings for Boats: What They Do and How to Apply Them
  • Inspect battery cables and terminals: tight, clean, no corrosion, boots on

    Every 6 months

    BoatUS: loose or corroded battery cables and terminals are the root of many DC problems; inspect all terminals and connectors regularly, clean corrosion with the power off, and protect posts with dielectric grease and insulating boots. Yamaha also lists cleaning battery terminals as routine care. BoatMend sets every 6 months (spring and layup); check more often in salt water. Hot, melted or charred cables: turn the battery switch off and call a marine electrician.

    How to Replace Boat Battery Cables the Right Way
  • Inspect dock lines and splices for chafe, broken fibers and loose whippings

    Every 3 months

    Samson: rope inspection is continuous, before, during and after each use; feel along every inch for broken fibers, abrasion, glazing and stiffness, and retire a rope before it breaks. BoatMend adds a closer look at splices, whippings and chafe guards every 3 months and before storms.

    Basic Rope Work for Boat Owners - Eye Splices, Whipping and Sealing Line Ends
  • Inspect prop shaft, strut, cutless bearing and propeller (out of water)

    Every year

    Check at each haul-out or before launch. Wiggle the shaft at the strut (play means a worn cutless bearing), check the prop for dings and the shaft seal or packing for drips. This is a common yearly haul-out check, not a manufacturer interval.

    How to Check the Cutless Bearing, Prop Shaft and Strut
  • Log engine hours (photo of the meter) and compare with the service schedule

    Every 1 months

    Discover Boating: boats count hours, not miles, and boats with consistent upkeep logs age better. Yamaha: total hours on its tachometers can't be reset, only trip and maintenance-interval counters. BoatMend suggests noting the hours monthly in season (or at each fuel-up) so hour-based services aren't missed.

    Engine Hour Meters: Why Hours Matter, How to Verify Them and How to Replace a Meter Honestly
  • Open and close every seacock; look for drips, stiffness and weeping at the hoses

    Every 1 months

    BoatUS (2025): inspect and exercise (operate) seacocks monthly; a frozen or stiff seacock should be serviced right away or replaced. BoatUS (2017): exercise them regularly (every couple of months at least) and lubricate at least once a year. Outboard boats with livewell or washdown seacocks benefit too. Never force a stuck handle with the boat in the water.

    How to Inspect and Exercise Seacocks, Through-Hulls and Hose Clamps
  • Test bilge pumps and high-water alarm (water must go overboard)

    Every 3 months

    BoatUS recommends testing every bilge pump and bilge alarm at least quarterly, and checking that water actually goes overboard instead of just listening for the motor to run. Lift each float switch (or add water) to check the automatic mode, try the manual switch, sound the high-water alarm and clear the strainer. This is in addition to the yearly spring check.

    How to Install a Backup Bilge Pump and High-Water Alarm

Every season

Spring commissioning, winterizing and yearly jobs.

  • At haul-out: check each thru-hull from outside while someone works the seacock, lubricate, and note hose ages

    Every October

    BoatUS (2025): during the annual haulout, shine a light into the thru-hull from outside while someone opens and closes it; look for leaks, cracks and broken bedding; a good general rule is to replace seacock hoses at 10 years regardless of condition. BoatUS (2017): lubricate seacocks at least once a year; cone and plug types must be disassembled. Replacement below the waterline is often a yard job.

    Replacing a Seacock or Through-Hull Fitting
  • Battery check and winter storage charge

    Every October

    Clean and tighten terminals, test state of charge, then fully charge and keep it on a maintainer (or disconnect it) for storage. A discharged battery can freeze. Mercury lists a battery check in its winterization checklist, and Yamaha's maintenance guide stresses battery care against corrosion. Re-test before launch in spring.

    Marine Battery Care: Test, Charge and Store for Winter
  • Check deck hardware, hatches and portlights for leaks

    Every April

    Look under every cleat, stanchion base, track, hatch and portlight for stains, drips, rust streaks or a soft deck around the fitting. Run a gentle hose stream over suspect spots with a helper below, the same hose test BoatUS suggests for cockpit drains. BoatUS warns that a leaking fitting can soak and rot a cored deck, so rebed early. Yearly is our suggestion; check again after heavy rain.

    How to Find and Fix Leaking Deck Hardware (Rebedding Cleats, Stanchions and Tracks)
  • Check hatch and seat gas struts: lid stays up on its own, no oil on the rod, fittings tight

    Every April

    SUSPA's gas spring FAQ: service life is finite (rated in thousands of strokes) and real life depends on the installation and conditions. A strut that no longer holds a hatch is a falling-lid injury risk. Yearly check is our suggestion; replace with the same force rating and length (see your old strut's label).

    How to Replace Gas Struts on Boat Hatches, Seats and Consoles
  • Check the damage control kit: plugs, wedges, sealant, tape, tools and bucket

    Every April

    BoatUS (2022): keep soft-wood plugs and wedges (pine or fir) that can be split and driven into a breach, along with other leak-stopping gear, where you can reach it fast. BoatMend suggests a yearly check that everything is there, in date (sealants and tapes) and stowed where the crew knows.

    How to Build a Damage-Control Kit: Plugs, Patches and a Plan for Leaks
  • Check the first-aid kit: expired and used items, dry case

    Every March

    The Red Cross says to check a first-aid kit regularly and replace anything used or past its expiration date. Restock medicines (seasickness, pain relief, antihistamine), sunscreen and waterproof bandages, make sure the case is still dry, and tell your crew where it is. Restock after any trip where you used it. Yearly is our suggestion.

    Boat First-Aid Kit and Medical Prep: What to Carry, Day Trips to Offshore
  • Check the onboard toolkit and spares (fuses, filter, prop hardware, batteries)

    Every April

    At commissioning (BoatMend's suggestion), make sure spares still match the engine, replace what you used last season, check flashlight and multimeter batteries and that sealants haven't cured in the tube. Discover Boating lists spare lines among the basics.

    Onboard Tool Kit and Spare Parts: What to Carry on a Day Boat or a Cruiser
  • Check throwable, boarding ladder and overboard-recovery gear; practice a pickup

    Every April

    Keep the throwable (ring, horseshoe or cushion) within arm's reach, not in a locker, and never use a cushion as a seat: the BoatUS Foundation says that breaks down the foam. Make sure the boarding ladder can be lowered by someone in the water and is not cracked or corroded; in BoatUS Foundation tests a ladder that worked on one boat often failed on another, so try yours. Check throw-bag lines, MOB lights and any sling. Practice a crew-overboard pickup at the start of the season. Yearly is our suggestion.

    Man-Overboard Recovery Gear: Throwables, Lifesling, Ladders and MOB Alarms
  • De-winterize and prepare for the season

    Every March

    Reinstall and charge the battery, check fuel lines and the fuel/water separator, check fluids, close drains and reinstall drain plugs, inspect hoses, clamps and belts, check the prop, then run the engine with cooling water and confirm the telltale or exhaust water flow before leaving the dock.

    Spring Commissioning - Getting Your Boat Ready for the Season
  • Flood-test cockpit scuppers, deck drains and their hoses

    Every April

    BoatUS suggests inspecting everything from each drain to the waterline at the beginning of every season, including livewells, bait wells and fish boxes, and running a hose into suspect areas to see where the water really goes. Claim files show missing clamps, broken drain fittings and loose or missing hoses; BoatUS also found many boats that sank in heavy rain because scuppers were overwhelmed and water got into the bilge through hatches.

    How to Inspect and Clear Cockpit Scuppers and Deck Drains
  • Fog engine for storage

    Every October

    Part of Mercury's outboard winterization checklist. Some fuel-injected and direct-injection engines have a specific storage or fogging procedure in the manual, so follow it rather than spraying into the intake.

    How to Fog an Engine for Storage
  • Fog readiness: test the horn or whistle, check nav and anchor lights, keep the fog-signal card at the helm

    Every April

    33 CFR 83.33: boats under 12 meters don't need a specific whistle or bell but must have some other means of making an efficient sound signal; 83.35 sets the fog signals (for example, one prolonged blast at least every two minutes for a powerboat making way). Mercury's fog tips: running lights on and the proper sound signals in restricted visibility. BoatMend suggests checking at season start that the horn works (wiring or air-horn canister), the lights work and a card with the fog signals is at the helm.

    Boating in Fog: When to Stay In, Sound Signals, Safe Speed and Using Your Electronics
  • Inspect anchor, rode, chain and shackles

    Every April

    Practical Sailor advises laying the whole rode out for inspection at least once a year. Look for a bent anchor, rust or worn galvanizing on the chain, chafed or stiff rope, and loose splices or thimbles. Shackle pins should be secured (moused) with stainless wire, not plastic ties. Turn chain end for end each year, and replace or regalvanize it once rust appears. Make sure the bitter end is tied to the boat.

    Anchor Basics: Choosing the Anchor, Rode and Scope, Setting It and Checking Your Gear
  • Inspect exhaust shutters/flapper valves (if fitted) for cracks, missing pieces and free movement

    Every October

    Boating Magazine (hydrolock article): exhaust shutters and flaps are one-way valves that keep water from sloshing back toward the cylinders; inspect them annually and replace as needed, because broken pieces can block exhaust cooling water. Easy on newer engines, a chore on older ones; a good time is riser or manifold service. Not every engine has them. Typical; confirm in your manual.

    How to Inspect and Replace Exhaust Shutters and Flapper Valves
  • Inspect hose clamps below the waterline and on fuel and cooling hoses: rust, slack, cracked housings

    Every April

    BoatUS (2014): give hoses a firm pull at the clamps, ideally out of the water, and look at the underside of each clamp, where corrosion usually starts. BoatUS (2024) covers choosing all-stainless marine clamps. BoatMend suggests a check at the start of every season and at each haul-out (our timing), and doubling clamps on below-waterline hoses where the fitting allows.

    Hose Clamps on Boats: Choosing, Installing and Inspecting Them
  • Inspect vented loop (anti-siphon) valves: clean off salt, check the rubber valve, replace every 3-5 years

    Every October

    West Marine: inspect the vented loop fitting yearly and replace it every three to five years, because the small rubber valve inside can harden or fail and the loop then gives no protection against seawater siphoning back into the engine (hydrolock). Keep the valve clean and free of salt buildup. Vented loops on marine head and bilge discharge lines deserve the same look.

    How to Inspect, Clean and Replace Vented Loops (Anti-Siphon Valves)
  • Record normal oil pressure (idle and cruise, engine warm) and check the oil level

    Every May

    BoatUS: low oil pressure comes from a low oil level, a clogged filter or, at worst, a failing oil pump; always believe the gauge and stop the engine. Knowing your own normal readings makes a drop easy to spot. BoatMend suggests writing them down early each season (our suggestion) and checking the dipstick before every outing. Confirm normal ranges in your owner's manual.

    Low Oil Pressure Warning: What to Do on a Sterndrive, Inboard or Diesel
  • Review the maintenance log: what's due, what keeps failing, what you spent; back up receipts and photos

    Every March

    Boating Magazine: log everything, including small jobs; the longer you keep a log, the more wear patterns from your own use show up, so you can replace a battery or cable before it strands you; track fuel and engine hours too; buyers check the log. Yearly review before commissioning is our suggestion.

    How to Keep a Boat Maintenance Log and Organize Your Receipts
  • Safety gear check: flares, fire extinguishers, PFDs, sound signal

    Every March

    Flares: pyrotechnic signals expire 42 months after manufacture, and expired ones don't count toward the requirement. Fire extinguishers: per the USCG, a disposable extinguisher more than 12 years past its manufacture date is expired; boats of model year 2018 and newer need date-stamped 5-B or 20-B units. Also check the gauge, PFD sizes, condition and count, and the horn or whistle. Follow federal and your state's rules.

    USCG Required Safety Equipment Check by Boat Length
  • Test bilge pump(s) and float switch, clean the bilge

    Every March

    Lift the float switch (or add water) to confirm the automatic mode works, check the manual switch, clear debris from the strainer, and check wiring and fuse. Should also be done regularly during the season, not just in March.

    How to Test and Clean Your Bilge Pump and Float Switch
  • Test navigation and anchor lights

    Every March

    Turn on each light, replace bulbs, and clean corroded contacts. Carry spare bulbs and fuses. PWCs are not included because they generally may not be operated at night.

    How to Test and Fix Your Boat's Navigation Lights
  • Winterize sterndrive / gas inboard

    Every October

    Mercury: complete the annual/100-hour service, stabilize fuel, then drain the seawater side (or fill it with antifreeze) and fog the engine following your manual. Keep sterndrives in the down position. Gas inboards follow the same idea; also drain or protect the transmission cooler and heater hoses.

    How to Winterize a Sterndrive (MerCruiser, Volvo Penta and Similar)

After every use

Quick habits that prevent the big repairs.

  • After a storm: check lines, chafe, bilge, covers and shore power before using the boat

    After every use

    Habit reminder after any big storm. NWS: stay away from downed wires and flooded areas until authorities say it's safe. BoatUS: document the damage with photos before moving anything and call your insurer early. Never board a boat with shore power that may be in contact with water; shut it off at the pedestal first or call a pro.

    After the Storm: How to Safely Inspect Your Boat and Document Damage
  • After each trip: gentle washdown of vinyl seats and cushions (no bleach, no pressure washer)

    After every use

    BoatUS: a gentle but thorough washdown at the end of every trip, even when the seats look clean, keeps sweat, dust and sunscreen from feeding mold. Use a soft mitt or sponge and mild boat soap, never a power washer, and keep bleach and high-alcohol cleaners away from the vinyl and the stitching; use a dedicated vinyl cleaner and protectant for tougher spots.

    How to Re-Cover Boat Cushions and Seats (DIY Sewing vs. Upholstery Shop)
  • Before leaving the dock: give the passenger safety briefing (life jackets, cut-off switch, extinguisher, VHF, man overboard, CO)

    After every use

    BoatUS Foundation: take a few minutes before departing to brief guests, so that if an emergency arises you have a team aboard; it offers a customizable predeparture checklist. Use the printable checklist in our guide; a short refresher is enough for regular crew.

    The Pre-Departure Safety Briefing: What to Tell Every Passenger (with a Printable Checklist)
  • Gasoline inboard/sterndrive: run the engine-compartment blower at least 4 minutes and sniff for fuel before every start

    After every use

    Federal rule 33 CFR 183.610 requires boats with a gasoline engine in a closed compartment to carry a label by the ignition: gasoline vapors can explode; before starting, operate the blower for 4 minutes and check the engine compartment bilge for gasoline vapors. If you smell fuel, don't start; find the leak or call a pro. Also listen for the blower running and feel for airflow at the exhaust vent now and then (see the bilge blower guide).

    Engine Room Ventilation: Combustion Air, Blowers and Keeping Salt Out
  • Look at the raw-water strainer before each trip (clean when needed)

    After every use

    A quick look through the clear bowl before each start shows weeds, shells or plastic before they starve the pump. BoatUS: if the strainer is below the waterline, close the seacock before opening it, empty and rinse the basket, make sure every gasket seats, reopen the seacock and run the pump to check that the bowl refills with no leaks. Raritan's clear-bowl design is meant for exactly this kind of at-a-glance check. Clean it more often in grassy or debris-filled water. This is a habit reminder, not a dated task.

    How to Inspect and Clean a Raw-Water (Sea) Strainer
  • Test the engine cut-off switch (lanyard or wireless) and wear it

    After every use

    With the engine idling in neutral and cooling water supplied, pull the lanyard clip (or trigger the wireless fob): the engine must stop. Many engine makers call for this before each use; BoatUS says to confirm each spring that the switch works and the lanyard is in good shape, and to refresh wireless fob batteries. Federal law requires using it on most boats under 26 feet when on plane. This is a habit reminder, not a dated task.

    Engine Cut-Off Switch (Kill Switch) and Lanyard: The Law, Testing and Daily Use

Only if your boat has it

Equipment-specific tasks. BoatMend adds these when your boat profile says you have the item.

  • Replace ballast pump impellers

    Every 100 h or every year, whichever comes first
    If you have: Ballast system

    Only for wake boats with impeller-type ballast pumps. MasterCraft: change ballast pump impellers every 100 hours as part of annual maintenance, and it recommends a dealer for the job. Running a pump dry wears the impeller fast. Some systems use aerator pumps without impellers. Typical; confirm in your owner's manual.

    Wake Boat Ballast Systems - Care, Troubleshooting, Weight Limits and Winterizing
  • Gyro stabilizer: replace the seawater-side zinc anode (models that have one)

    Every 200 h or every 3 months, whichever comes first
    If you have: Gyro stabilizer

    Seakeeper's maintenance schedule: replace the zinc anode every 200 running hours or 3 months, whichever comes first, on the Seakeeper 5, 6, 9, 16, 18, 26, 35 and 40. Other models and brands differ; follow your unit's manual.

    Gyro Stabilizer Care: Owner Checks for Seakeeper and Other Boat Gyros
  • Gyro stabilizer: yearly inspection (hydraulics, brake bushings, cooling and glycol, seawater flow, wiring, mounting bolts)

    Every 1000 h or every year, whichever comes first
    If you have: Gyro stabilizer Pro recommended

    Seakeeper's schedule, every 1,000 hours or annually: inspect hydraulic parts and hoses, brake bushings, heat exchanger, cooling hoses and glycol level, electrical connections and mounting hardware; clean and descale the heat exchanger and confirm seawater flow. It also lists flushing the glycol circuit every 2,000 hours or 5 years. Seakeeper points owners to its annual inspection bulletin; most owners have a certified dealer do it.

    Gyro Stabilizer Care: Owner Checks for Seakeeper and Other Boat Gyros
  • After fishing: rinse fish boxes, clear scales from the drain and run the pump until the water goes overboard clear

    After every use
    If you have: Fish box macerator

    Sportsman Boats: scales and fish waste build up in the box and attract odors and pests; regular maintenance of the macerator pump and hose prevents it. Switch the pump's breaker off before reaching into the box. Make sure the outlet goes overboard, not into the bilge.

    Fish Box Drains and Macerator Pumps: Clogs, Check Valves and Odor Control
  • At haul-out: inspect bottom paint for wear, flaking, thick buildup and blisters; plan touch-up or repaint

    Every October
    If you have: Antifouling paint

    BoatUS (bottom paint): boats that stay in the water most of the season need bottom paint; hard paints build up over the years until they crack and peel and the hull must be stripped (see our bottom-paint-stripping guide). Interlux: check that a new paint is compatible with the old one before you recoat. Never use copper paint on aluminum hulls or drives. Yearly look at haul-out is our timing.

    Bottom Paint (Antifouling): Do You Need It, Which Type, and How to Repaint
  • Battery monitor: make sure it has synced to 100% on a full charge and its readings make sense

    Every 1 months
    If you have: Battery monitor

    Victron (SmartShunt manual): the state of charge must resynchronize regularly with the battery's true state to stop it drifting; this happens automatically when the battery reaches full charge as defined by the charged-voltage, tail-current and detection-time settings. If the monitor hasn't seen a full charge in a while, give the bank a full charge. Practical Sailor's test found monitors need setup adjustments to read accurately. Monthly check is our suggestion; settings come from your monitor's and battery's manuals.

    Battery Monitors with a Shunt: Installing, Setting Up and Reading State of Charge
  • Before heading out: holding tank pumped out or with room, Y-valve or overboard thru-hull locked closed where discharge is banned

    After every use
    If you have: Marine head

    BoatUS (2016): regular pump-outs keep room in the tank; in No Discharge Zones the macerator's overboard thru-hull should be locked shut unless the Y-valve is locked. An open thru-hull can also let water flow back into a below-waterline tank. EPA lists No Discharge Zones by state.

    How to Use a Pump-Out Station: Finding One, Hooking Up and Rinsing the Tank
  • Before launch: drain plug in and snug (and a spare aboard)

    After every use
    If you have: Trailered

    Mercury's pre-tow checklist: make sure the drain plug is in the tow vehicle along with the keys before you leave home. Boating Magazine suggests carrying a spare garboard plug or two because they are easy to lose. Check that the plug is in and tight before the boat goes in the water, and pull it again for trailering and storage (see Clean, Drain, Dry).

    Drain Plugs: Types, Pre-Launch Checks, Spares and Replacing a Garboard Drain
  • Brush underwater light lenses and check for leaks inside

    Every 1 months
    If you have: Underwater lights

    OceanLED recommends cleaning the lens at least once a month with a soft boat brush: growth dims a light in weeks. Never scrape a dry lens, use a metal scraper, solvents or a pressure washer. While you're at it, look inside the boat around each through-hull light housing and cable for water.

    Underwater LED Lights: Care, Leaks, Corrosion, Wiring and the Rules
  • Built-in fuel tank: check fill cap O-ring, sender gasket and screws, and the tank for corrosion

    Every April
    If you have: Built in fuel tank

    BoatUS (2025): most water gets into fuel through a few points that need periodic inspection, such as the fill cap O-ring, which dries and cracks, and the sending unit gasket and screws. BoatMend suggests a yearly look, with a fuel sample. Fuel smell or wet tank: stop and call a pro.

    How to Inspect Your Boat's Fuel Tank, Fill, Vent and Hoses
  • Cabin heater: pre-season check and service, CO alarms tested

    Every October
    If you have: Cabin heater Pro recommended

    Before the heating season: test every CO alarm, check the heater exhaust or flue joints, through-hull or deck fitting, air intake and fuel line, and have fuel-burning heaters serviced on the maker's schedule. The UK MAIB found that a fatal CO case came from an owner-fitted diesel heater whose silencer was not marine-rated or gas-tight, had never been checked by a professional or serviced, in a boat with no CO alarm. BoatUS notes natural-draft heaters need a permanently open fresh-air supply and CO and smoke alarms in the main cabin and every sleeping area.

    Cabin Heater Safety Aboard: Diesel, Propane and Electric Heaters
  • Chainplates: lift, clean and reseal the deck cover plates; inspect the chainplates for rust and cracks

    Every October
    If you have: Sailboat

    The Rigging Company (Annapolis) says the deck cover plate is only there to seal and should be lifted, cleaned and resealed every two to three years, give or take, depending on location and use, to keep water out of the deck core and the cabin. Practical Sailor recommends a yearly DIY rig check (see the rig inspection task) and, for offshore boats, a professional rig survey every three to five years.

    How to Inspect Sailboat Chainplates for Leaks, Cracks and Hidden Corrosion
  • Check flare expiration dates and condition before the season

    Every March
    If you have: Pyrotechnic flares

    Pyrotechnic signals expire 42 months after manufacture (about every three seasons), and an expired signal does not count toward the federal requirement on coastal waters and the Great Lakes. Orion says to replace any that will expire during the coming season and to inspect all signals and launchers for moisture damage at least once a year. Dispose of old flares through your fire department or a collection event, never overboard or in the trash.

    Visual Distress Signals: Flare Expiry, Storage, Practice and Safe Disposal
  • Check the Coast Guard Certificate of Documentation expiration date and renew directly with the NVDC

    Every year
    If you have: USCG documented

    46 CFR 67.163: a recreational endorsement lasts 1 to 5 years, as chosen at issue or renewal. The NVDC home page (October 2026) says all documentation and payments go through its online eStorefront and that third-party renewal companies don't act for the Coast Guard. BoatMend reminds you yearly to check the expiration date and the managing owner's address on file (changes must be reported within 30 days under 46 CFR 67.113 and 67.319). A state registration and decal may still be due separately (see registration-renewal).

    USCG Documentation Renewal: When, How, What It Costs and How to Avoid Look-Alike Renewal Mailers
  • Check the keel-hull joint and keel bolts at haul-out (and after any grounding)

    Every year
    If you have: Sailboat

    Practical Sailor advises inspecting keel bolts at each haul-out or after a grounding; obvious warning signs include large gaps at the keel joint and weeping rust stains. Photograph the joint and every keel nut from the same angles each year. After a real grounding, BoatUS says a sailboat needs a professional inspection. Re-torquing, pulling bolts and dropping the keel are yard jobs.

    Sailboat Keel Bolts and the Keel-Hull Joint: Signs of Trouble and What to Do
  • Check the shore power cord, plugs and inlet for heat damage, corrosion and chafe

    Every 1 months
    If you have: Shore power

    BoatUS: turn off the boat's main AC breaker and the pedestal breaker, unplug both ends, and check the cord for chafe, cracks and repairs, and the plugs and inlet for discoloration or corroded pins, each time you disconnect or monthly at a minimum. Any burned or melted plug: don't reconnect; call a marine electrician.

    Shore Power Cord Ends: How to Judge a Cord, and When to Replace the Plug or the Whole Cord
  • Clean and polish clear enclosure panels (isinglass)

    Every 1 months
    If you have: Canvas enclosure

    Rinse clear panels with fresh water after every outing and never wipe off dry salt or dirt. Strataglass recommends its cleaner every 1-2 weeks and its polish every 1-2 months (more often when the panels are new), and says unapproved products can damage the panels and void the warranty. Use only what your vinyl maker approves.

    How to Clean and Care for Clear Vinyl (Isinglass) and Polycarbonate Enclosure Panels
  • Clean and sanitize the freshwater tank and lines

    Every April
    If you have: Freshwater tank

    Practical Sailor recommends cleaning the freshwater tank once a year, or twice a year in hot climates. Pull carbon filters first, dose plain unscented bleach by tank size, push it through every faucet (hot and cold), leave it for the contact time, then flush until the taste is gone and fit new filter cartridges. Also do it after buying a used boat, after a long layup and whenever the water smells or tastes off.

    How to Clean and Sanitize Your Boat's Freshwater Tank and Lines
  • Clean stainless hardware, treat tea staining and look for cracks or rust weeping

    Every 3 months
    If you have: Saltwater

    Practical Sailor: a regular freshwater rinse is usually all stainless needs, with passivating after damage. BoatMend suggests a deeper clean and inspection every few months in salt water. Rust weeping from a fitting or a crack in rigging or rail bases: have it checked.

    How to Clean, Protect and Inspect Stainless Steel Boat Hardware
  • Clean, Drain, Dry before leaving the ramp

    After every use
    If you have: Trailered

    Stop Aquatic Hitchhikers: in every waterbody, every time, clean plants, animals and mud off the boat, trailer and gear, drain the motor, bilge, livewell and other water-holding spaces before leaving the access, and let everything dry before the next launch. Many states require drain plugs out on the road and run inspection stations; follow your state's rules. Wake boats must drain their ballast tanks too.

    Clean, Drain, Dry: Stopping Zebra and Quagga Mussels and Other Invasive Species
  • Compression test (older gas engines, or before buying or selling)

    Every 2 years
    If you have: Older engine

    BoatUS says compression tests are particularly useful on older engines. On an engine more than about 10 years old, a test every couple of seasons builds a record that shows wear before it leaves you stranded; also test before you buy or sell. Write down the date, hours and every cylinder's reading, and compare cylinders with each other. Diesel compression tests need special gauges and are a mechanic's job. The interval is our suggestion.

    How to Do a Compression Test on an Outboard, Sterndrive, Inboard or PWC
  • Electric furler: rinse the swivels, check the drum, control switch and wiring

    Every April
    If you have: Electric furler

    Harken: the halyard and tack swivels need minimal maintenance and can be cleaned by flushing with detergent and fresh water; its sealed motor and gearbox need no maintenance. Check your own furler's manual. BoatMend suggests doing it at spring commissioning, with a look at connectors and the deck switch for corrosion.

    Electric and Hydraulic Headsail Furlers: Care, Manual Override and Safety
  • Engine room fire suppression system: yearly inspection (gauge or weight, actuator, shutdown)

    Every April
    If you have: Fixed fire system Pro recommended

    BoatUS: installed engine compartment systems must stay accessible for removal, weighing and inspection, and an older halon system can stay in service only as long as it passes its annual inspection. Check the gauge or weight per the maker, the manual pull, the engine shutdown and the helm indicator, and have a qualified service company inspect and recharge it as the maker requires.

    Engine Room Automatic Fire Suppression: How It Works, Checks and What to Do After a Discharge
  • EPIRB/PLB check: self-test, battery and hydrostatic release dates

    Every March
    If you have: EPIRB PLB

    Run the self-test exactly as the beacon maker describes (NOAA allows self-tests without approval; never press ON to test). Check the battery expiry label and, on float-free EPIRBs, the hydrostatic release unit date; AMSA notes most disposable HRUs are marked for replacement 2 years after installation. Inspect the case, antenna and bracket. Some makers suggest a more frequent self-test; follow your manual and its limit on the number of tests.

    EPIRB and PLB Care: Registration, Batteries, Self-Test and Mounting
  • Galley stove and propane: inspect hoses, locker drain and lid seal, solenoid, and leak-test with the gauge or soapy water

    Every April
    If you have: Galley stove

    BoatUS (propane, 2018): propane is heavier than air and collects in the bilge; cylinders belong in a sealed locker above the waterline with a drain overboard at its lowest point; hoses must be an approved type, regularly inspected for chafe and splits, with permanent fittings (never hose clamps); a pressure gauge helps leak checks. Yearly check is our suggestion; smell for gas before every use. If you smell propane, shut it off, no switches, ventilate and get off the boat.

    Galley Stove Safety: Propane, Alcohol and Electric Cooktops Aboard
  • Holding tank deep clean: pump out, rinse and treat to remove scale and odor

    Every October
    If you have: Marine head

    BoatUS (2024): the best practice is to treat and clean the tank regularly so scale doesn't build up, and to tell apart a one-time 'shock' treatment from routine small doses for odor. BoatMend suggests a full pump-out, rinse and treatment once a year at layup, plus regular pump-outs. Use only products your toilet and tank makers approve; never discharge in a No Discharge Zone.

    How to Deep Clean a Boat Holding Tank
  • Ice maker: run the maker's cleaning cycle, sanitize and check the water filter

    Every 6 months
    If you have: Ice maker

    U-Line: ice machines need regular cleaning so scale and buildup don't wear the evaporator and condenser; follow the cleaning notification and the steps in your model's guide, using approved cleaners. BoatUS notes boat water systems need periodic treatment and flushing. BoatMend suggests every 6 months and before the first use after storage.

    Ice Makers and Drinking-Water Dispensers on Boats: Cleaning, Filters and Winterizing
  • Inflatable life jacket inspection (leak test, cylinder, inflator)

    Every March
    If you have: Inflatable PFD

    USCG: maintain inflatables per the maker's instructions. Mustang: visual check before every use (service indicator green, cylinder tight), and every 6 months an overnight oral-inflation leak test plus a check of the cylinder and the date on the auto-inflator's bobbin or cartridge. Do at least a full inspection each spring; many makers want the leak test more often. Typical; confirm in your life jacket's manual.

    Inflatable Life Jacket Care: Inspect, Test and Rearm
  • Inspect exhaust manifolds and risers for corrosion and leaks

    Every year
    If you have: Raw water cooled4-stroke Pro recommended

    Most important on raw-water-cooled engines, especially in saltwater. Corroded risers can let water into the cylinders and wreck the engine. Look for rust streaks, weeping gaskets and restricted flow. Replacement timing depends on use and water type (often 5-7 years in saltwater), and the inspection is usually done by a pro. Not an official interval.

    How to Inspect Exhaust Manifolds and Risers on a Sterndrive or Inboard
  • Inspect exhaust risers/elbows on closed-cooled engines

    Every year
    If you have: Closed cooling4-stroke Pro recommended

    BoatUS points out that even with a freshwater (closed) cooling system, exhaust risers are still cooled by raw water and need regular inspection. Its rough guide is to remove and inspect risers yearly once they are three to five years old in salt water, and less often in fresh water; outside rust or weeping means it is past time. Usually a job for a pro.

    Closed-Cooled Gas Engines: Why the Exhaust Elbows Still Need Checking
  • Inspect fuel fill and vent hoses, clamps and deck fill (built-in tanks)

    Every April
    If you have: Built in fuel tank

    Once a year at spring commissioning (BoatMend's suggestion), open the access panels and check the fill and vent hoses for cracks, softness, fuel smell and rusty clamps. A BoatUS surveyor notes the generally accepted norm is to replace rubber fuel hoses over about 10 years old regardless of appearance. Fuel smell or wet hose: stop and call a pro.

    How to Inspect and Replace Boat Fuel Fill and Vent Hoses
  • Inspect mast, standing rigging and chainplates

    Every year
    If you have: Sailboat

    BoatUS recommends inspecting standing rigging at least once a year (some parts monthly in heavy use) and having rigging more than 10 years old professionally inspected every year until it is replaced. The easiest time is when the mast is down for storage or trailering (see the mast stepping guide). Look for cracked or rust-stained terminals, broken strands, missing cotter pins, bent turnbuckles, chainplate leaks and a corroded mast step.

    How to Inspect Your Sailboat's Standing Rigging
  • Inspect rudder, rudder tube seal and steering gear

    Every April
    If you have: Has rudder

    For boats with rudders (sailboats and inboard powerboats). Edson's steering inspection checklist (on Jacobe Marine's support page) calls for a yearly inspection by the owner or a service center: cables (cotton-ball test for broken strands), tension with the wheel hard over, sheaves and alignment, quadrant clamp and rudder stops, chain, bearings and lubrication. BoatUS describes a cable that parted after years without maintenance, something a yearly check would likely have caught. Also check the rudder tube seal for leaks and test-fit the emergency tiller.

    Rudder, Rudder Bearings and Steering Gear Inspection (Sailboats and Inboards)
  • Inspect the bow eye, transom tie-down eyes, inside nuts and backing plate, and the winch strap

    Every April
    If you have: Trailered

    BoatUS (winch strap article): replace a strap with frayed stitching, cuts, tears, twists or heavy fading before it fails at the ramp. BoatUS (backing plates, 2020): hardware without a backing plate concentrates the load and can pull through. BoatMend suggests a yearly look at the bow eye's inside nuts and backing plate (photo them to compare) plus a glance at the eye and strap every time you hitch up (our timing).

    How to Inspect and Replace Your Bow Eye and Transom Eyes
  • Inspect trailer axle, leaf springs, hangers, shackles and U-bolts

    Every March
    If you have: Trailered

    For trailered boats. Look for broken or rust-thinned leaves, cracked hanger welds, worn shackles and bushings, loose or rusted U-bolts and rust-through on the axle tube. Dexter says bent hangers, springs or axle tubes cause bad alignment and tire wear, and warns not to jack on suspension parts. Discover Boating notes that uneven tire wear can mean a bent axle. On torsion axles, check the frame mounting bolts. Easy to do at the yearly hub service.

    How to Inspect Boat Trailer Axles, Leaf Springs and Hangers
  • Inspect trailer brakes and surge actuator fluid

    Every year
    If you have: Trailered

    Each season: keep the brakes clean (rinse with fresh water after salt launches), check the brake fluid in the actuator's master cylinder and test the brakes before a long trip. Discover Boating says to have the pads or shoes inspected every few seasons; if you launch in salt water, yearly is a good idea. Drum and caliper work is usually a trailer shop job.

    How to Check and Care for Boat Trailer Surge Brakes
  • Look over the galvanic isolator and its connections (shore power boats)

    Every April
    If you have: Shore power

    BoatUS: follow the maker's maintenance; in most cases check the unit and its connections for corrosion or physical damage at least once a year. Anodes wasting away suddenly can point to a failed isolator. Testing and any work on the AC green ground is a job for an ABYC-certified marine electrician.

    Galvanic Isolator: Why Shore-Powered Boats Need One and How to Tell If It's Working
  • Low-voltage disconnect: check its settings, status light and connections, and that bilge pumps are not behind it

    Every April
    If you have: Low voltage disconnect

    Victron Smart BatteryProtect: the operating mode (buzzer/LED, relay, or Li-ion with an external BMS) sets how it alarms and disconnects; pick Li-ion mode only if your BMS has a load or charge disconnect output. Blue Sea: 24-hour circuits such as bilge pumps and alarms should be wired so they can't be switched off by accident, so they must never sit behind a load disconnect. Yearly check is our suggestion; voltages and modes come from your device's manual.

    Low-Voltage Disconnects: Keep the Stereo and Fridge from Killing Your Battery
  • Marine head: hose rag test, shock the holding tank, check joints

    Every year
    If you have: Marine head

    BoatUS suggests shock-treating the holding tank at least once a year (spring or fall) and doing the rag test on sanitation hoses: wipe a low section with a warm, damp cloth, seal it in a plastic bag, take it into fresh air and sniff. A smelly rag means the hose is permeated and should be replaced. Check every clamp and joint for stains or drips. Raritan suggests its hose descaler every few months, more often with seawater flushing or slow drainage.

    Smelly Head Hoses: How to Test, Choose and Replace Sanitation Hose
  • Marine head: monthly vinegar flush and pump lube

    Every 1 months
    If you have: Marine head

    BoatUS suggests running a pint of white vinegar slowly through the head once a month to dissolve fresh scale, flushing with fresh water, then adding a marine toilet lubricant (or mineral oil) to keep the pump's rubber parts supple. When a manual head gets hard to pump, lets water back into the bowl or leaks at the shaft, rebuild it with the maker's service kit. Use only cleaners your toilet maker allows.

    How to Rebuild a Manual Marine Toilet (Hand-Pump Head)
  • Monthly exhaust system check (CO prevention)

    Every 1 months
    If you have: CO alarm

    USCG carbon monoxide checklist: once a month, make sure exhaust clamps are tight and look for rust or black streaks, water leaks, and cracked or corroded fittings; check rubber exhaust hoses for burned, cracked or stiff spots. Have a technician inspect the exhaust system and water pump impellers once a year.

    Carbon Monoxide on Boats: Where It Comes From, CO Alarms and Warning Signs
  • Outriggers: inspect poles, bases, pulleys and halyards; lubricate and tighten; replace worn rigging line

    Every April
    If you have: Outriggers

    Rupp: rinse outriggers with fresh water after every trip, replace missing bushings, tighten loose bolts, lubricate moving parts with approved products and check rigging and hydraulic fittings. Discover Boating: rigging lines degrade from sun and salt and should be replaced every couple of seasons. Marlin: a pro can remove and inspect them during the annual yard visit. Stay clear of overhead power lines with outriggers up.

    Outrigger Care: Poles, Halyards, Release Clips and Bases
  • Pre-tow check: hitch, chains, lights, straps and tire pressure

    After every use
    If you have: Trailered

    Mercury's pre-tow checklist: coupler fully on the ball, latched and pinned; safety chains crossed under the tongue; every trailer light working; transom tie-downs and winch strap tight with the winch safety chain hooked; trailer tire pressure checked, because trailers sit between trips and lose air. Also support or tilt the engine the way your manual says. This is a habit reminder, not a dated task.

    Get Your Boat Ready for the Road: Pre-Trailering Checklist
  • Press TEST on the boat's ELCI (shore power main breaker) and every GFCI outlet, then reset

    Every 1 months
    If you have: Shore power

    ELCI breakers have a built-in test feature like household GFCIs (Cruising World). BoatMend follows the monthly test most makers print on ELCI and GFCI devices: with shore power on, press TEST; it must trip and cut AC power, then reset it. If it doesn't trip, stop using shore power and have it replaced. If it trips by itself, don't keep resetting it: find the fault (see the ELCI guide). BoatUS also advises having the boat's AC system inspected and tested yearly. Never swim near a boat or dock with shore power connected.

    ELCI Retrofit: Adding Whole-Boat Shock Protection to an Older Boat
  • Press the test button on each CO alarm

    After every use
    If you have: CO alarm

    USCG carbon monoxide checklist: test each CO alarm by pressing its test button every time you go on a boat trip. Never ignore an alarm. This is a habit reminder, not a dated task.

    Carbon Monoxide on Boats: Where It Comes From, CO Alarms and Warning Signs
  • Private dock or lift: press TEST and RESET on every GFCI

    Every 1 months
    If you have: Private dock

    CPSC: test GFCIs monthly to make sure they work. Press TEST (power should cut off), then RESET. A GFCI that won't trip, or trips by itself, means stop using that circuit and call a licensed electrician. Never swim near a dock with power on.

    Electrical Safety at Your Private Dock or Boat Lift: GFCI, Shock Drowning and Annual Checks
  • Private dock or lift: yearly inspection by a qualified electrician

    Every April
    If you have: Private dock Pro recommended

    BoatUS: have a qualified marine electrician inspect your private dock annually. Safe Electricity: dock electrical work should be done by a professional familiar with marine codes and inspected at least once a year. Log the date and any faults fixed.

    Electrical Safety at Your Private Dock or Boat Lift: GFCI, Shock Drowning and Annual Checks
  • Pull trailer hubs, inspect and repack wheel bearings, replace seals

    Every year
    If you have: Trailered

    Dexter (a major axle maker): remove the hubs every 12 months or 12,000 miles to inspect the bearings, and always fit new grease seals so grease can't leak onto the brakes. E-Z Lube style spindles let you purge water between services, but they don't replace the yearly inspection. Sealed cartridge bearings (such as Nev-R-Lube) follow their own schedule. Typical; confirm with your axle maker.

    How to Inspect and Repack Boat Trailer Wheel Bearings
  • Radar: clean antenna, check mount, cable and connectors, confirm bearing alignment

    Every April
    If you have: Radar

    A yearly look at spring commissioning (BoatMend's suggestion; makers don't set an interval). Breaker off and tagged before going near the antenna. Wash the radome or array gently, check the mount bolts, follow the cable for chafe and open reachable connectors for corrosion. BoatUS warns never to cut the plug off a radar cable, since damaged shielding hurts performance. Raymarine's bearing-alignment check: point the bow at a fixed object and see that it sits under the heading line.

    Recreational Radar Care: Radome and Open-Array Cleaning, Mounts, Cables and Alignment
  • Re-check each child's life jacket: right size and weight range on the label, snug fit, crotch strap, no damage

    Every April
    If you have: Children aboard

    BoatUS Foundation: every person aboard needs a Coast Guard-approved life jacket in serviceable condition and of the appropriate size. Coast Guard: adult life jackets may not work for children; child sizes exist, and state wear rules for kids vary. Kids grow, so BoatMend suggests a fit check every season and whenever a child has a growth spurt (our timing).

    How to Choose and Fit Life Jackets for Children and Babies
  • Reefing system: wash reef lines, check for chafe at blocks and clews, and test that each reef ties in smoothly

    Every October
    If you have: Sailboat

    BoatUS: during the season dirt and salt work into ropes, making them stiff and abrading internal fibers; washing by hand in a bucket with soap or in a washing machine on a gentle cycle removes them. Check with the rope maker first for high-tech lines. Doing it at layup and practicing a reef at the start of each season is our suggestion.

    How to Maintain Your Mainsail Reefing System and Practice a Reef at the Dock
  • Remove and inspect lifelines; check stanchions, bases, pelican hooks and lashings

    Every April
    If you have: Sailboat

    BoatUS (2024, surveyor Frank Lanier): remove all lifelines annually and inspect them for kinks, wear, damage and corrosion, especially at end fittings and where the wire passes through stanchions; replace end lashings annually; vinyl-coated wire should be replaced about every five years regardless of how it looks. Also check stanchion bases for loose fasteners and deck leaks.

    How to Inspect Sailboat Lifelines, Stanchions and Gates
  • Renew NOAA EPIRB/PLB registration (every 2 years) and update contacts

    Every 2 years
    If you have: EPIRB PLB

    NOAA says a 406 MHz beacon registration is valid for only two years and must be renewed; update it sooner whenever your phone, address, emergency contacts or boat change. Registration is free (never pay anyone to register). The online database has planned maintenance outages now and then (one was announced for October 27, 2026, up to 48 hours), so do not leave it to the day before a trip; NOAA also accepts its forms by email, fax or mail.

    EPIRB and PLB Care: Registration, Batteries, Self-Test and Mounting
  • Renew state registration and put on the new validation decals

    Every March
    If you have: State registered

    BoatUS: registration is usually renewed every year or two, depending on the state; check the expiration on your certificate and adjust this interval. Allow time for decals by mail before the first trip. Documented boats renew with the Coast Guard NVDC instead.

    Boat Registration Numbers and Validation Decals: Federal Display Rules, State Placement and Renewals
  • Replace closed-cooling coolant (check level yearly)

    Every 2 years
    If you have: Closed cooling4-stroke

    Indmar chart: check coolant every 300 hours or yearly and change it every 2 years. Also inspect and clean the heat exchanger yearly. Mercury lists 5 years with extended-life coolant, so follow your engine's manual.

    How to Check and Change Coolant in a Closed Cooling System
  • Replace CO alarm at end of life

    Every 5 years
    If you have: CO alarm

    USCG: replace alarms as the alarm maker recommends. Fireboy-Xintex marine CO detectors, for example, start an end-of-life warning just before 5 years from activation and must then be replaced. Other brands differ, so set this to the date printed on your alarm.

    Carbon Monoxide on Boats: Where It Comes From, CO Alarms and Warning Signs
  • Review your MMSI registration (contacts, emergency contacts, boat description) and confirm every DSC radio and AIS uses it

    Every April
    If you have: DSC radio

    NAVCEN: MMSI registration data goes to the Coast Guard so rescuers can identify and locate you, so update it whenever contact or vessel information changes; registrars email reminders to update and confirm it every two years. Sea Tow accounts were moved to the U.S. Power Squadrons. Also update it right away after a sale, rename or new phone number.

    FCC Ship Station License vs. a Free MMSI: Which One Your Boat Needs, and How to Keep It Current
  • Rinse the bimini and canvas with fresh water; check stitching, snaps and frame

    Every 1 months
    If you have: Bimini canvas

    Sailrite: rinse outdoor Sunbrella items every month; a thorough cleaning is usually needed only every two to three years. Garden hose only, no pressure washer, and let it dry before stowing. Loose frame fittings or torn straps: fix before running with the top up.

    How to Replace or Re-Cover a Bimini Top
  • Sailboat spring commissioning: rig, sails, through-hulls, systems and safety gear

    Every April
    If you have: Sailboat

    BoatUS (2025): start commissioning with a written list and reevaluate it every season. Rig and through-hull checks first, then engine, plumbing, electronics and safety gear before launch.

    Sailboat Spring Commissioning: Rig, Sails, Bottom, Engine and First Sail
  • Satellite messenger: confirm subscription is active, charge it and send a test message

    Every April
    If you have: Satellite messenger

    Garmin: SOS and Garmin Response come only with an active inReach subscription. Before the season, confirm the plan, update contacts and firmware, charge fully and send a non-SOS test message. Never press SOS to test. A messenger doesn't replace a registered 406 MHz PLB or EPIRB (see the EPIRB/PLB tasks).

    Satellite Messenger vs PLB vs EPIRB: Which Emergency Device Should You Carry?
  • Shore power inlet: clean the contacts, look for heat marks and do a heat check under load

    Every April
    If you have: Shore power

    BoatUS: 55 percent of boat fires start in the electrical system and the shore power inlet is a major source, because corroded or arc-damaged blades heat up; it recommends keeping connectors clean and not connecting or disconnecting with power on. BoatMend suggests a start-of-season check: with power off, look for discoloration or melting at the inlet and plug, then after an hour under normal load feel the cord end and inlet for warmth. Any heat, browning or a loose fit: stop using it and have a marine electrician replace the inlet and plug. The monthly cord check (shore-power-cord-check) still applies.

    Shore Power Inlet and Cord Upgrades: Burned Plugs, Better Connectors and Safe Adapters
  • Solar check: clean panels, connectors, fuse and controller settings

    Every April
    If you have: Solar panels

    Rinse salt off the panels, inspect for cracks, delamination and hot spots, check MC4 connectors and the deck fitting, confirm the fuse near the battery, and make sure the charge controller's battery profile matches your batteries. Note midday output and compare with last year. Victron's manual lists the normal reasons for low output (battery already full, cold lithium battery, voltage drop in the wiring, hot controller) before blaming a panel. Rinse more often on a saltwater boat.

    How to Care for Boat Solar Panels, Connectors and the Charge Controller
  • Synthetic teak deck: wash with mild soap along the grain and check edges and seams for lifting

    Every 1 months
    If you have: Synthetic teak

    Flexiteek: its anti-fungal additives work best when dirt, sunscreen, food and standing water are rinsed away routinely. PlasDECK's cleaning guide covers a deeper clean with a degreaser left 5 to 10 minutes and a brush along the grain. Rinse after every trip; BoatMend suggests a monthly wash and a look at edges, seams and fittings for lifting. Lifting or bubbling under warranty: call the installer.

    Synthetic Teak Decking: Choosing, Installing and Caring for PVC Teak
  • Teak deck: inspect the caulked seams for gaps, lifting and loose plugs

    Every April
    If you have: Teak deck

    Teak Decking Systems: a teak deck lasts with gentle regular cleaning, periodic sealing and prompt re-caulking when seam deterioration appears; avoid acid cleaners, pressure washing and abrasive tools. BoatMend suggests a seam check each spring; failed seams let water reach the core and fastenings.

    How to Re-Caulk Teak Deck Seams (and When the Deck Is Beyond Saving)
  • Test cabin smoke and heat alarms; note the replacement date

    Every 1 months
    If you have: Smoke alarm

    BoatUS and the U.S. Fire Administration both say to test smoke alarms monthly with the test button. USFA: replace the whole alarm every 10 years (sooner aboard if damp or vibration affect it, and follow the maker). Change replaceable batteries at least yearly.

    Smoke and Heat Detectors on a Boat: Where They Make Sense, What to Buy and How to Test
  • Test the gasoline fuel vapor detector (helm test button, maker's sensor test)

    Every 1 months
    If you have: Fuel vapor detector

    BoatUS: vapor alarms should be tested monthly using the manufacturer's procedure. Press the helm test button (lights and horn), then test the sensor only the way the maker allows. A detector is not a substitute for running the blower and sniffing the engine space before every start. Any fuel smell: don't start anything, get everyone off and call a pro.

    How to Check and Test a Gasoline Vapor (Fume) Detector
  • Tow vehicle pre-season: towing (severe-service) schedule, transmission fluid, brakes, tires, hitch receiver bolts and wiring plug

    Every March
    If you have: Trailered

    BoatUS (Tow Package Or Not): factory tow packages add transmission and engine cooling, wiring and hitch hardware because towing stresses the engine, transmission and brakes; use Tow/Haul mode. BoatUS (Preparing to Tow, 2015): good tread, no weather cracks and correct tire pressure are vital. Follow your vehicle manual's towing or severe-service schedule; rinse salt off the underside after saltwater launches.

    Tow Vehicle Maintenance for Boat Owners (Transmission, Differential, Brakes, Hitch)
  • Tow vehicle: drain and check the rear differential gear oil at the end of the season if the rear axle goes in the water at the ramp

    Every October
    If you have: Trailered

    BoatUS (2013): water can get into a differential through the vent tube or condensation, and submerging the rear axle at the ramp doesn't help; owners who back their rear tires into the water should drain the rear differential fluid at least at the end of every boating season and look for milky or yellow-brown oil. Refill with the lube in the vehicle's owner's manual (limited-slip units may need an additive).

    Tow Vehicle Rear Differential Care: Ramp Water, Milky Gear Oil and Limited-Slip Additive
  • Trailer brakes (EOH/electric): check breakaway battery charge and test the breakaway switch

    Every March
    If you have: Trailer electric brakes

    BoatUS: EOH systems include a battery box with a 12-volt battery for the breakaway system. Check the charge at the start of each season and before long trips, then pull the pin briefly (trailer hitched and chocked) and put it right back. For commercial trailers the FMCSA rule (49 CFR 393.43) requires breakaway brakes to stay applied at least 15 minutes, a useful yardstick.

    Electric-Over-Hydraulic and Electric Trailer Brakes: Controller Setup, Breakaway and Care
  • Trailer check: wheel bearings, tires, lights, winch and straps

    Every March
    If you have: Trailered

    For trailered boats only. Yamaha's checklist: grease the bearings, make sure lug nuts are tight and not rusting, check tire tread and pressure, and inspect the winch. Also test the lights and brakes, and check the safety chains, coupler and tie-downs.

    How to Inspect a Used Boat Trailer Before You Buy
  • Trailer guide-ons: tighten U-bolts and brackets, check posts for bends and rust, carpet or rollers, and guide-on lights

    Every April
    If you have: Trailered

    BoatUS (guide-on install, 2020): sturdy guide-ons bolt to the trailer frame with U-bolts and help center the boat in wind and current; flimsy bolt-on guides can't take a bow bouncing off them. BoatMend suggests a yearly check of the mounting hardware and lights at season start (our timing). Never reach in to push a moving hull off a post.

    How to Choose, Install and Adjust Trailer Guide-Ons (Posts or Bunks)
  • Treat head discharge hoses with a maker-approved descaler

    Every 3 months
    If you have: Marine head

    Raritan: clean hoses every few months, more often with salt-water flushing or slow drainage (BoatMend sets 3 months). Use only a descaler approved for your toilet and hoses, follow the label, and keep up the monthly vinegar routine in between.

    How to Prevent and Remove Scale in Marine Toilet Discharge Hoses
  • Water heater: inspect anode and relief valve at layup

    Every October
    If you have: Water heater

    BoatUS's author inspects the water heater anode each winter at layup and replaces it when more than half gone; glass-lined tanks depend on it, while some stainless tanks have no anode. Relieve pressure and switch the breaker off first, never power the element until the tank is full again, and check that the relief valve is not dribbling afterward. Confirm with your heater's manual.

    Marine Water Heater Care: No Hot Water, Relief Valve, Anode and Winter Draining
  • Watermaker: fresh-water flush after each use; flush every few days or pickle when it sits

    After every use
    If you have: Watermaker

    Spectra: flush the system with fresh water after every use and change prefilters regularly. Practical Sailor: a watermaker that isn't used regularly must be flushed with fresh water about every five days or pickled, and pickling must be repeated about every six months if it stays unused. Follow your maker's procedure and chemicals.

    Watermaker Care: Pre-Filters, Flushing, Pickling and Production Checks
  • Winter afloat visit: bilge, lines, snow, de-icer and GFCI

    Every 1 months
    If you have: Winter in water

    For boats left in the water over winter. On each visit check the waterline and bilge, the bilge pump and battery charge, dock lines and chafe gear, snow on the cover, and that the de-icer runs with open water around the hull. Press the GFCI test button: Kasco recommends GFCI protection and says no one should ever enter the water while a de-icer is running. BoatUS claim files show boats sink at the dock more than twice as often as underway. Monthly is our suggestion; visit after every storm or cold snap too.

    How to Keep Your Boat in the Water Over Winter (De-Icers, Covers and Checks)
  • Winterize the sailboat: rig, sails, plumbing, hull and auxiliary engine

    Every October
    If you have: Sailboat

    Discover Boating: even sailboats without an engine or plumbing need hull, rigging and interior preparation before winter. Do the engine tasks from its own winterizing task, then sails, running rigging, water and head systems, and ventilation under the cover.

    How to Winterize a Sailboat: Rig, Sails, Engine, Plumbing and Storage

Get this plan built for your boat

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