When a genset drops out, the vessel loses air conditioning, galley, hotel load and sometimes its departure. We diagnose and repair marine generator sets on board — engine side, alternator side and control side — with proper load testing before hand-over.
Marine generator sets fail in three different domains, and the biggest waste of downtime is diagnosing the wrong one. The diesel engine, the alternator and the control and protection system each produce their own symptoms — and a set that trips on overload, hunts under load or refuses to take up load can be any of the three. We work across all of them, so the diagnosis is not limited by what the visiting engineer happens to know.
| Interval | Work |
|---|---|
| 250 – 500 h | Oil and filters, coolant test, raw water impeller, belts, air filter, leak check, alarm and shutdown test, insulation resistance measurement. |
| 1,000 – 2,000 h | Valve clearances, injector service, turbocharger inspection, anodes, heat exchanger cleaning, alternator bearing and coupling check, mount inspection. |
| Annual | Load bank test to rated output, exhaust and cooling survey, control system function test, emergency genset statutory checks. |
| Overhaul hours | Top-end or full engine overhaul, alternator reconditioning, control panel refurbishment. See overhaul. |
Superyacht gensets frequently run at a fraction of their rating for long periods — a 100 kW set carrying 20 kW at anchor. Chronic light running causes incomplete combustion, glazed liners, carbon build-up in the turbocharger and exhaust, and unburnt fuel and oil in the exhaust system, known as wet stacking. The set then cannot take full load when you need it, and often trips on the first heavy demand.
We test sets against a resistive load bank up to rated output, recording temperatures, pressures, voltage, frequency and power factor throughout. That verifies the repair, proves the emergency set will perform in a survey, and often reveals a capacity problem that no amount of dockside running would have shown.
Generator sets built around Caterpillar / CAT, Cummins, MAN and MTU diesel engines, with the alternator and control equipment commonly fitted to them. Alignment of engine to alternator is covered on our alignment page. We are an independent service company and not an authorised dealer or official service partner of any engine or genset manufacturer.
Usually load acceptance rather than a fault in the load: a governor or fuel delivery limit on the engine side, an AVR or excitation limit on the alternator side, or a set that has lost capacity through light running and carbon build-up. Load testing separates the three.
Most often injection condition, air restriction, a fouled turbocharger or exhaust back pressure from wet stacking after long periods at low load. All are measurable rather than guessable.
Yes, using a resistive load bank. It is the only reliable way to prove capacity and the only test that satisfies most survey requirements for emergency sets.
We diagnose the alternator, measure insulation resistance and check bearings, AVR and coupling, and carry out repairs or arrange specialist rewinding where the machine needs workshop attention.
Same-day advice by phone or WhatsApp, and mobilisation within days for most European locations. Call +31 6 20743967 with the set details and the vessel location.
Send the details below and you will hear back from an engineer, not a call centre. For a vessel that is stranded or on a tight departure slot, call +31 6 20743967 or message us on WhatsApp.
Send the make, model, running hours and the alarm shown. We will tell you what is most likely, what parts to have ready, and when we can be on board.
Urgent attendance when the vessel has lost power or a departure is at risk.
→ Read more MaintenanceMain engines and gensets serviced on the same visit.
→ Read more AlignmentEngine-to-alternator alignment and mount renewal.
→ Read more