boat.lifeBoat maintenance schedule: tasks by calendar and engine hours
Most boat maintenance is due either after a certain time or after a certain number of engine hours, whichever comes first. A clear schedule turns a vague feeling of "I should probably check that" into a short list of what is due this season. The intervals below are typical starting points. Always follow your engine and equipment manufacturer's manual where it differs.
Task by interval
Use the calendar interval for boats that run few hours, and the engine-hour interval for boats that run a lot. Whichever comes first decides.
| Task | Calendar interval | Engine hours | Notes |
|---|---|---|---|
| Engine oil and oil filter | Every year | 100 to 250 h | Change warm, before winter storage |
| Fuel filter and water separator | Every year | 200 to 300 h | Drain the separator bowl more often |
| Raw water impeller | Every 1 to 2 years | 200 to 300 h | Carry a spare on board |
| Coolant (closed system) | Every 2 to 5 years | 1,000 h | Check level every trip |
| Drive belts | Inspect yearly, replace every 3 to 5 years | 500 h | Replace if cracked or glazed |
| Gearbox or drive oil | Every year | 100 to 200 h | Milky oil means water ingress |
| Saildrive or sterndrive bellows and seals | Inspect yearly, replace every 5 to 7 years | - | Follow the drive maker's interval |
| Anodes | Every year | - | Replace at 50 percent wear |
| Antifouling | Every 1 to 2 years | - | Depends on water and paint type |
| Seacocks and through-hulls | Exercise yearly, inspect hauled out | - | Should turn freely |
| Batteries | Check every season, replace every 4 to 6 years | - | Charge fully before storage |
| Standing rigging | Inspect yearly, replace every 10 to 15 years | - | Sailboats, survey before replacing |
| Life jackets and liferaft | Inspect yearly, liferaft service per maker | - | Check gas cylinders and auto-inflators |
| Fire extinguishers | Check yearly | - | Pressure gauge in the green |
Winterization
Done well in autumn, winterization prevents most of the expensive surprises in spring.
- 1Change engine oil and filter while the engine is warm.
- 2Flush the raw water system with fresh water, then with antifreeze.
- 3Fill the fuel tank and add stabilizer to reduce condensation.
- 4Remove or loosen the impeller to prevent it taking a set.
- 5Drain fresh water tanks, water heater and pipes, or add potable antifreeze.
- 6Charge batteries fully and disconnect or put them on a maintenance charger.
- 7Clean and dry the interior, open lockers and ventilate to prevent mildew.
- 8Take photos of anything that needs repair so it ends up on the spring list.
Spring commissioning
Work through the boat before launch, while everything is easy to reach.
- 1Inspect the hull, replace anodes and apply antifouling.
- 2Check seacocks, hose clamps and stern gland or shaft seal.
- 3Refit the impeller and check belts, hoses and coolant level.
- 4Reinstall and test batteries, lights, bilge pumps and navigation electronics.
- 5Check safety gear: life jackets, flares, extinguishers and first aid kit.
- 6Start the engine after launch and check for leaks and cooling water flow.
- 7Log what you did, with date and engine hours.
Keep the schedule and the log together
A schedule only works if you record what was done. Read how to keep a good boat maintenance log, and what each entry should contain.
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