Main Engine 4-Stroke · Main Engines (4-Stroke)
The Cummins QSK50 Marine is a medium‑speed V‑16, 4‑stroke diesel main propulsion engine delivering up to ~1860 kW (≈2500 hp) at 1500–1950 rpm, noted for its modular common‑rail fuel system and IMO Tier II/III emissions compliance.
Do you have the manufacturer datasheet for this model? Send it with the enquiry form — we check it and name the source.
What our service work and the manufacturer documentation say about keeping this model running.
Maintain by Cummins marine schedule with oil sampling, filters, valve train, injectors and cooling system checks.
| Engine Oil & Filter Change | 250-500 hours (or annually, whichever comes first, based on oil analysis) |
|---|---|
| Fuel Filters (Primary & Secondary) | 250-500 hours (or annually, based on differential pressure) |
| Air Filters | 500-1000 hours (or as indicated by restriction gauge) |
| Valve Lash Adjustment | 1000-2000 hours |
| Injector Inspection/Service | 3000-6000 hours (or as indicated by performance issues) |
| Coolant System Flush & Replenish | 2000-4000 hours (or every 2-3 years, based on coolant analysis) |
| Turbocharger Inspection | 1000-2000 hours (external visual, internal at major service) |
| Engine Mount Inspection | Annual or 500 hours |
Typical intervals for this design class, not the manufacturer’s figures for your model. The manufacturer’s manual is binding.
| Cylinder Liner Wear (Max Ovality/Taper) | 0.05 - 0.10 mm over nominal bore (159mm) |
|---|---|
| Crankshaft Main Bearing Clearance | 0.08 - 0.15 mm |
| Connecting Rod Bearing Clearance | 0.08 - 0.15 mm |
| Piston Ring End Gap (Top Ring) | Max 1.0 - 1.5 mm |
| Valve Stem to Guide Clearance | Max 0.10 - 0.20 mm |
| Turbocharger Shaft End Play | Max 0.10 - 0.15 mm (axial) |
| Turbocharger Shaft Radial Play | Max 0.20 - 0.30 mm (radial) |
Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.
Class surveyors will typically focus on regulatory compliance, safety, and structural integrity. Key checks include: verification of engine operating parameters against design specifications; functional testing of all safety devices (overspeed, low oil pressure, high coolant temperature shutdowns); inspection of fuel oil system for leaks, fire hazards, and proper isolation; examination of exhaust system for integrity, insulation, and fire safety; inspection of engine mounts and foundation for structural integrity; verification of alarm and monitoring systems; review of engine maintenance records and oil analysis reports; and, depending on the survey type (e.g., special survey), potential for opening up components for internal inspection (e.g., cylinder heads, bearings) based on running hours and condition.
Estimated lifetime: 20,000 - 30,000 hours before major in-frame overhaul (top-end, bearings, liners)
Common spares: filters, injectors, sensors, water pump kit, belts and turbocharger parts.
Free of charge — send us your request for Cummins equipment. Our team checks it and replies by e-mail.
Other models of the same equipment type, Cummins first.
Tell us what you need for this Cummins QSK50 Marine — a part, a service call, a second opinion. Are you Cummins? Claim this brand page.
Service engineer? Write the day report for this QSK50 Marine in OceanSphere Work — photos, hours and parts, as a PDF for the owner. Try it free for 14 days →
Yes. Specifications, documents and service notes for this model are readable without an account. An account adds saved searches and requests, nothing is taken away.
Yes. Tell us the manufacturer, the model and what you need — a person reads every request and replies by e-mail.
Send us the nameplate or the correct value. We check it against the manufacturer datasheet or class-society record and update the page.