Recommissioning After Layup in Australia
Most marine engine failures happen in the first hours of the season, not the last. Recommissioning is the service that finds them at the dock instead of at the heads, and it is the highest-value work in the marine calendar.
→ Winterisation and seasonal layup
Why the first trip is the dangerous one
Everything that degraded over the layup is still fine while the engine sits. It only becomes a failure when the engine is asked to work:
- Settled tank sludge is stirred up by the first seaway and blocks the filters
- The impeller, set against the cam, does not pump properly under load
- Perished hoses fail under pressure and vacuum
- A flat or sulphated battery will not restart the engine after the first stop
- Marine growth in the raw water intake restricts flow once demand is high
- Seals that dried out leak once warm
None of that is visible at the berth with the engine idling.
What recommissioning covers
Before starting:
- Confirm every seacock and closure sealed during layup is dealt with. Removing exhaust and intake bungs matters — running an engine with a blocked exhaust does immediate damage.
- Impeller inspected or replaced, and the strainer cleaned
- Belts and hoses checked for perishing and softness
- Fuel filters and water separator serviced, and a tank bottom sample taken
- Oil level and condition, coolant level and condition
- Batteries load tested
- Engine bay inspected for rodent and insect damage to wiring
On start-up:
- Confirm water flow at the exhaust within seconds
- Temperature and oil pressure watched to operating condition
- Listen and look for leaks — fuel, oil, coolant, exhaust
Under load:
- A run at sustained cruise, long enough to reach thermal equilibrium
- Confirm the engine reaches rated wide open throttle RPM
- Check gearbox engagement and temperature
- Check charging under load
→ Sea trial and engine performance testing
The sea trial is the part people skip and the part that finds things. An engine that idles perfectly at the berth can still overheat and starve for fuel twenty minutes into a passage.
If the boat sat with untreated fuel
Expect filter problems and plan for them. Carry spares, and consider having the fuel tested or polished before the season rather than discovering the state of the tank offshore.
→ Fuel polishing and tank cleaning
What it costs
Find recommissioning in your city
Frequently asked questions
Why do so many failures happen on the first trip of the season? Because layup damage only reveals itself under load. The engine that idles perfectly at the dock is a different proposition twenty minutes into a passage.
Isn’t starting the engine enough of a test? No. Fuel starvation, overheating, gearbox slip and charging faults appear under sustained load and nowhere else.
What should I check first after a layup? That every bung, seal and closure fitted during layup has been removed — especially the exhaust — and that water flows at the exhaust within seconds of starting.
My boat sat all winter with an untreated tank — what now? Assume filter problems. Sample the tank, carry spares, and consider polishing before the season rather than mid-passage.