Yacht maintenance schedule — by engine hours and by season
8 min read
A whole-boat maintenance schedule for a 30–100 ft yacht: which jobs run on engine hours, which run on the calendar, and a table you can copy straight into your own plan.
Two clocks run on every boat. Engines, generators and anything with an impeller wear by the hour; everything else — rigging, canvas, safety gear, anodes, the hull — wears by the season. A schedule that mixes the two up is either done too late or done too often. This guide splits them, gives typical intervals for each, and shows how to turn it into a plan the crew can follow. For the engine-only detail, see our guide to setting service intervals by hours.
Rule one: hours or months, whichever comes first
Every hour-based item also has a calendar limit, because oil degrades, coolant goes acidic and impeller rubber hardens whether the engine runs or not. A boat that did 80 hours this year still needs its annual oil change. Write both limits against each item and let the earlier one win.
The hour-based schedule (engines, generators, drives)
| Item | Hours | Calendar limit |
|---|---|---|
| Engine oil and filter | 250 | 12 months |
| Generator oil and filter | 250 | 12 months |
| Fuel filters, primary and secondary | 250 | 12 months |
| Raw-water impeller | 250 | 12 months |
| Drive belts — inspect / replace | 250 / 1,000 | 24 months |
| Gearbox, saildrive or sterndrive oil | 250–500 | 12 months |
| Heat exchanger and engine anodes | 500 | 12 months |
| Air filter | 500 | 12 months |
| Valve clearances | 500–1,000 | per manual |
| Coolant flush and replace | 1,000 | 24 months |
| Exhaust and mixing elbow inspection | 1,000 | 24 months |
| Injectors and turbo inspection | 2,000 | per manual |
| Outboard: oil, gear oil, impeller, spark plugs | 100 | 12 months |
The season-based schedule (everything else)
These jobs do not care how many hours the engines did. Plan them around the two natural stops in the year — commissioning and lay-up, or in warm-water fleets, the start and end of the charter season — plus a monthly pass in between.
| Item | Interval | Notes |
|---|---|---|
| Bilge pumps and float switches | Monthly | Test each one by lifting the float |
| Sea cocks, thru-hulls, hose clamps | Monthly operate; annual service | Two clamps per connection below the waterline |
| Batteries: terminals, water, load test | Monthly; load test annually | Replace at 5–7 years or on a failed test |
| Steering: play, hydraulic fluid, cables | Monthly | Full lock to lock |
| Windlass and winches | Monthly operate; annual strip and grease | Listen for grinding |
| Anodes (hull, shaft, prop, trim tabs) | Every haul-out; check visible ones monthly | Sooner in marinas with stray current |
| Antifoul and hull inspection | 12 months | Prop, shaft, cutless bearing, rudder bearings |
| Standing rigging inspection | 12 months (professional) | Replace at 10–15 years or per insurer |
| Running rigging and sails | Seasonal | Chafe, stitching, UV strips |
| Canvas, covers, biminis | Seasonal | Clean, re-proof, zips |
| Liferaft service | 12 months (or per manufacturer, up to 3 years) | Keep the certificate on board |
| Flares | Expiry date, typically 3 years | Dispose of correctly |
| EPIRB battery and hydrostatic release | Per unit, typically 5 and 2 years | Registration must be current |
| Fire extinguishers and fixed system | 12 months | Weigh or gauge check |
| Gas system: hoses, regulator, detector | 12 months | Hoses dated; replace at 5 years |
| Watermaker membranes and filters | Filters monthly in use; membranes 3–5 years | Pickle for lay-up |
| Fridge and A/C: strainers, coils, gas | Monthly strainers; annual service | Clean condenser coils |
| Registration, insurance, radio licence, crew certificates | Expiry dates | Renew 30 days ahead |
Building the plan from these two tables
- Copy every row into your own schedule with the boat's actual last-done date and hours against it. An interval without a last-done is not a schedule.
- Give each item an owner. On a two-person boat that is still worth doing: the engineer takes the hour-based list, the mate takes the calendar list.
- Group the calendar jobs into two big weeks a year (commissioning and lay-up) and one short monthly pass; do not spread them evenly or they get skipped.
- Reorder the parts for a service a month before it is due, so the service happens on the date, not when the filter arrives.
- Review the intervals after the first year. If an impeller is perfect at 250 hours in your water, keep it; if it is chewed at 200, shorten it.
Do all of this in iVessel — and more
iVessel holds both clocks for you: log the hours as you shut down, and it works out what is due on hours and what is due on the calendar, and reminds you before either slips.
- Put every item above on a schedule by hours, by date or both; iVessel tracks last-done, calculates next-due and shows overdue items across the fleet at a glance.
- Build your own checklists for the monthly pass, commissioning and lay-up, in the order you want — stored on the boat's account, never lost with a crew change.
- Assign jobs and checklists to a crew member; each item is signed off with a name and a time, so you see who did what.
- Log the parts used as you go and the spares inventory is updated automatically; reorder lists write themselves.
- Works offline at sea and syncs when you are back in range. iOS, Android and web.
Your first boat is free for 30 days.
Frequently asked
How often should a yacht be serviced?
Engines and generators every 250 running hours or 12 months, whichever comes first; the rest of the boat on a monthly pass plus two larger seasonal services (commissioning and lay-up), with annual checks of safety gear, rigging, hull and anodes. Manufacturer intervals override these where published.
Should a maintenance schedule be based on engine hours or dates?
Both. Engine and generator items wear by the hour but also degrade with time, so each gets an hours interval and a calendar limit, and the earlier one applies. Everything else on the boat is scheduled by the calendar.
How do I keep a maintenance schedule from being forgotten?
Record the last-done date and hours for every item, give each item an owner, and use something that calculates next-due and reminds you — a spreadsheet only works if someone remembers to open it.
Track this in iVessel — free 30-day trial
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