Mitsubishi engine models covered
Spare parts supply across the Mitsubishi marine diesel programme — from large-bore UEC slow-speed 2-stroke main engines to the S-series four-strokes, which the builder's own product guide splits into high-speed engines (the SA/SR series, S6R among them) and medium-speed engines (the SU series, S6U among them) for propulsion, auxiliary and diesel-electric duty.
UEC33LSE
UEC33LSE RFQs can include cylinder liners, pistons, exhaust valves and fuel injection pumps. Confirm serial/build, installed configuration and part evidence.
UEC37LA
UEC37LA RFQs can include piston rings, cylinder heads, stuffing-box seals and crosshead bearings, with any turbocharger line quoted from the turbocharger's own plate. Confirm build evidence.
UEC45LA
UEC45LA RFQs can include liners, piston crowns, exhaust valves, fuel injection equipment and camshaft-drive components. Confirm the approved overhaul scope and build evidence.
UEC50LSE
UEC50LSE RFQs can include cylinder-liner kits, piston assemblies, exhaust valve spindles and seats, and crankpin and crosshead bearings. Where the plate carries an Eco suffix, as in 6UEC50LSE-Eco-B1, copy it in full: on a UE engine, Eco marks the electronically controlled build.
UEC52LA
UEC52LA RFQs can include main bearings, crankpin shells, cylinder heads, fuel injection pumps and plungers, and governor components. Confirm build evidence.
UEC60LS
UEC60LS RFQs can include pistons, liners, exhaust valves, turbocharger interface parts, stuffing-box seals and overhaul gasket kits. Confirm build evidence.
S6U-MPTK
S6U-MPTK RFQs can include cylinder heads, piston kits, connecting rod bearings, injection nozzles, turbocharger parts and cooling-system spares. Confirm serial/build and generator-set evidence.
S6R-MPTK
S6R-MPTK RFQs can include cylinder-liner kits, valve seat inserts, fuel injection pumps, governor parts and gasket sets. Confirm serial/build and generator-set evidence.
Mitsubishi marine spare parts supply scope
Planned overhaul components, running spares, and time-critical spare parts — structured by system and component group for Mitsubishi UEC 2-stroke main engines and S-series 4-stroke auxiliaries.
- Cylinder liners & piston rings
- Piston crowns & skirts
- Cylinder heads & head gaskets
- Exhaust valves, seats & spindles
- Fuel injection pumps & plungers
- Fuel injector nozzles & holders
- Turbocharger cartridges & nozzle rings on non-MET machines (a MET unit is quoted from its own plate on the MET page)
- Main bearings & crankpin shells
- Crosshead bearings & pins
- Camshaft bearings & drive components
- Stuffing box seals & piston rod packings
- Connecting rod bearings & bolts
- Governor & speed control parts
- Overhaul gasket kits & seal sets
One maker name, three separate parts routes
Mitsubishi is not one supply route but three, and which one a request belongs to is decided by the plate rather than by the name. Getting that wrong sends a line to the wrong catalogue before anything is priced.
- Full engine designation as stamped, with the cylinder count and every suffix — 6UEC50LSE, not UEC50
- Whether the machine is a UE two-stroke or an S-series four-stroke, since the two have different design owners and different catalogues
- On an S-series engine, the model with everything after the hyphen — S6R2-T2MPTK, not S6R — because the code after the hyphen gives the emission standard (T2 for IMO Tier II, Y2 for EPA, G2 for China's GB, none for IMO Tier I) and the MPTK, MPTA or MPTAW ending says whether the charge-air cooler takes sea water, fresh water or an external cooling circuit
- The builder named on the plate, which for a UEC is often a licensee rather than the design owner
- Engine serial or build number and the year of build
- Cylinder number the component came off, for any running-gear item
- On a two-stroke, whether the line is a cylinder liner, a piston crown, an exhaust valve spindle or a complete cage — four items that a request often names as one
- Part number and the parts-book page it came from, treated as a starting point rather than a conclusion
- Bearing shells with the undersize stated, and ring sets quoted per cylinder rather than per ring
- Turbocharger designation from its own plate, since a MET machine is quoted from its own catalogue
- Photographs of the engine nameplate and of the component in place
Tools for this equipment: the Pt100 and thermocouple reader for the temperature sensors, the pressure gauge selector for the engine gauges and the O-ring size finder for loose O-rings. A bunker grade such as an RMG or a DMA, or a trade name such as VLSFO, is decoded by the marine fuel grade reader. For a UEC main engine, the admiralty coefficient calculator relates the power to the ship speed and gives the power for a new speed by the cube law. For a performance check on a UEC engine, the indicated power calculator works out the indicated power from the pmi, the bore, the stroke and the speed, and the mechanical efficiency against the shaft power.
Route comparison for Mitsubishi engine parts.
OEM-route and verified alternative routes are reviewed side by side so buyers can choose the route that fits approval needs, documentation, lead time and budget logic.
Cost-Aware Supply Options
On a UEC the split usually runs along the running gear: piston rings, stuffing-box packings, gaskets and O-rings are where a verified alternative is most often worth reviewing, while a liner, piston crown or exhaust valve spindle going back into a class-surveyed engine normally stays on the OEM route. Each quoted line states which route it is on.
OEM or Alternative — Your Choice
For class-surveyed overhauls or warranty-sensitive repairs, OEM-route review can be requested. For running spares and planned maintenance intervals, verified alternative routes can also be reviewed.
Lead Time Confirmed at RFQ Stage
Lead time, availability and freight options are confirmed at RFQ stage based on part specification, approval requirements, vessel ETA and destination port.
Technical Part Identification
When part numbers are missing, complete engine designation, serial/build, component description, nameplate photographs and drawing or part-book evidence can start identification review. Final identity is confirmed only from sufficient evidence.
Port-Aware Delivery Planning
Supply route, handover option and freight timing are reviewed against confirmed RFQ details, vessel ETA, port context, documentation needs and part availability before quotation. No fixed delivery commitment is made before availability and route are confirmed.
Time-Critical Priority Review
Main engine failures on vessels with Mitsubishi UEC slow-speed engines receive priority RFQ review. Time-critical RFQs are checked against supplier availability, freight options, vessel timing and port timing.
Mitsubishi parts — common questions
Can Vessel Core review OEM-route and verified alternative routes for Mitsubishi UEC engines?
Yes. We review OEM-route and verified alternative routes for Mitsubishi UEC series 2-stroke slow-speed engines and for S-series four-stroke requests, whether the engine drives a generator or a propeller. Alternative routes are selected case by case where documentation, quality and approval status permit.
What Mitsubishi engine models do you cover?
RFQs may reference Mitsubishi UEC33LSE, UEC37LA, UEC45LA, UEC50LSE, UEC52LA, UEC60LS, S6U-MPTK or S6R-MPTK configurations. Provide exact serial/build and part evidence; availability and route are confirmed only in the quotation.
How is lead time set for Mitsubishi spare parts?
We confirm lead time and freight in the quotation. A UEC large-bore item, such as a liner, a piston crown or an exhaust valve spindle, and an S-series genset consumable rarely move on the same clock, so we quote them as separate lines and put a date against each only once a supplier has committed to it.
Can Vessel Core supply Mitsubishi parts if I only have the engine type designation?
If an exact part number is unavailable, engine designation, serial/build, component description, plate photos and drawing or part-book evidence can start identification review. No component is confirmed from model family or dimensions alone.
Our UEC engine plate says Mitsubishi. Is it still a Mitsubishi design?
Not any more. The UE two-stroke design passed to Japan Engine Corporation (J-ENG) on 1 April 2017, so a UEC engine is a J-ENG design today whatever the nameplate says, and it has long been built under licence by other engine works, Kobe Diesel and Akasaka in Japan and Hyundai Heavy Industries in Korea among them, whose name may be the one on the plate. The S-series four-strokes stayed in the Mitsubishi group and since 2016 have come from Mitsubishi Heavy Industries Engine & Turbocharger (MHIET). MET turbochargers are a third business again: a nozzle ring or rotor line belongs on the MET turbocharger page rather than with the engine.
How is a designation such as 6UEC50LSE read?
The leading digit is the cylinder count, 50 is the bore in centimetres and LSE marks the generation; the other UEC generations are written LSII, LSH and LSJ. Send the whole string as stamped, with every suffix, 6UEC50LSE rather than UEC50 and the Eco suffix where the plate carries one, and say whether the engine is a UE two-stroke or an S-series four-stroke, since the two have different design owners and different catalogues.
Is Vessel Core connected to Mitsubishi Heavy Industries or Japan Engine Corporation?
No, and there is no agreement of any kind. Vessel Core holds no dealership, distribution, representation or partnership agreement with Mitsubishi Heavy Industries or Japan Engine Corporation, and quoting a component against one of their designations implies no approval by the maker and no claim of interchangeability.
Why the maker name appears on this page
UEC and S-series designations, and the corporate names behind them, appear here because a request cannot be described without them. None of it implies appointment. Vessel Core holds no dealership, distribution, representation or partnership agreement with Mitsubishi Heavy Industries, with Japan Engine Corporation, or with any other manufacturer referenced on this site.
Submit your RFQ now.
Send your Mitsubishi spare parts request — vessel name, engine model (e.g. Mitsubishi UEC45LA), part numbers or descriptions, and port/ETA. Vessel Core reviews the supply route and prepares a structured supply quotation.
