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Cummins · Independent specialists

Cummins marine engine repair and service.

Diagnosis, repair, maintenance and overhaul on Cummins marine propulsion engines and generator sets — QSK, QSM, QSB, KTA and older N-series — carried out on board across Europe.

Families
QSB · QSC · QSM · QSK · KTA
Also
Cummins-based gensets
Work
Repair · Service · Overhaul
Status
Independent — not a dealer
Experience

Cummins engines are honest, well-documented engines to work on

Cummins marine diesels turn up throughout the fleet: QSB and QSC in tenders, chase boats and smaller yachts; QSM11 and QSK19 in larger yachts, workboats and pilot vessels; KTA and N-series in older commercial installations that are still working hard. Parts support is strong, service data is detailed and the engines respond very well to disciplined maintenance — which also means most faults we see are traceable to fuel, cooling or a deferred service item rather than to the engine design.

Independent service provider. Superyacht Engine Service is an independent marine engineering company. We are not an authorised dealer, official service partner or representative of Cummins Inc. or its distributors. The Cummins Inc. or its distributors name and model designations are used purely to describe the equipment we service, and all trademarks remain the property of their respective owners. For warranty work or factory-authorised service, contact the manufacturer's official network.
Engine families

Cummins marine engines we work on

FamilyTypical modelsWhere you find them
QSB / QSC / QSLQSB6.7, QSC8.3, QSL9Tenders, chase boats, smaller yachts, auxiliaries
QSMQSM11Yacht propulsion, workboats, commercial craft
QSKQSK19, QSK38, QSK50Larger yachts, shadow vessels, heavy commercial propulsion and power generation
Legacy mechanicalKTA19, KTA38, NT/NTA855Older commercial vessels and generator sets
Common work

What we are typically called in for

  • Fault codes, derates and limp modes — read out, then confirmed against pressures, temperatures and flows before any part is ordered.
  • Fuel system work — high-pressure common rail and unit injection service, injector testing, lift pump and filtration problems, water in fuel and microbial contamination.
  • Aftercooler and turbocharger — a classic Cummins marine wear point: aftercooler core corrosion and fouling, boost loss, oil carry-over and back pressure.
  • Cooling circuit — seawater pumps, impellers, heat exchangers, thermostats and coolant condition, including inhibitor depletion in engines that sit idle.
  • Head and valve work — valve and injector setting to Cummins procedure, head reconditioning, gasket and liner sealing.
  • Top-end and in-frame overhauls — liners, pistons, rings, bearings and running gear to specification, with measurement records. See overhaul.
  • Generator sets — Cummins-powered gensets including load bank testing. See generator repair.
On aftercooled Cummins marine engines, aftercooler condition is worth checking before chasing a power complaint anywhere else. A fouled or leaking core costs power, raises exhaust temperatures and, if it leaks internally, puts seawater where it must never be.
Approach

Diagnose, document, then repair

Every job produces a record: readings taken, values found, parts fitted and recommendations for the next interval, written per vessel. Combined with scheduled maintenance, oil analysis and an alignment check after any drivetrain work, that is what keeps a Cummins installation reliable at high hours.

Questions we get asked

Frequently asked questions

Which Cummins marine engines do you repair?

QSB, QSC, QSL, QSM11 and the QSK family (QSK19, QSK38, QSK50), plus legacy mechanical engines such as KTA19, KTA38 and NTA855, and Cummins-powered generator sets. Send the model and serial for confirmation.

My Cummins is in a derate — can you diagnose it remotely?

Often we can narrow it substantially by phone or WhatsApp: the code, the conditions in which it appears and a few readings from the crew usually identify the system involved. That decides whether a visit is needed and what parts to bring.

Do you service Cummins aftercoolers?

Yes — cleaning, pressure testing and renewal. On engines used in warm seawater or left standing, aftercooler corrosion is one of the most common causes of lost power and high exhaust temperatures.

Can you overhaul a Cummins engine in the vessel?

Top-end and in-frame overhauls are routinely done in situ where access allows, with liners, pistons, rings and bearings renewed to Cummins tolerances and every measurement recorded.

Are you an authorised dealer for this brand?

No. We are an independent marine engineering company and we say so plainly. We service, repair and overhaul these engines on their technical merits; for factory warranty work or authorised-network service, go to the manufacturer’s official dealer. Many owners and managers use us alongside the dealer network — independently for service and repair, and through the dealer where warranty requires it.

Do you use genuine parts?

We source genuine and OEM-equivalent parts through established marine suppliers, and we tell you which is which. On critical internal components we recommend genuine parts; on many service items a quality equivalent is sound engineering at a better price. The choice stays yours.

Service enquiry

Tell us about the engine and the vessel.

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.

Direct line

Cummins fault you want a second opinion on?

Send the model, running hours and the fault codes. We will tell you what the code actually points at and what we would measure first.

Superyacht Engine Service — powered by Marine Service Altena B.V.
+31 6 20743967 · info@superyachtengineservice.com
KvK 99330911 · Available for callout across Europe
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