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MerCruiser 4.5L MPI Engine Parts

MerCruiser

4.5L MPI engine parts

4.5L MPI

Find parts for Mercury-built MerCruiser 4.5L MPI V6 sterndrive engines. Match the exact model, engine serial number and installed emissions, control and cooling equipment.

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Service & maintenance

Start your parts search

Collections are browsing aids and include parts for other engines. Confirm the complete model, serial number and exact assembly before ordering.

Engine maintenance collectionBrowse collectionEngine maintenanceBrowse Mercury and MerCruiser service and maintenance parts.Browse collection Cooling system collectionBrowse collectionCooling systemBrowse pumps and cooling components; match the exact assembly.Browse collection Fuel system collectionBrowse collectionFuel systemBrowse fuel-system components; confirm installed equipment.Browse collection

Browse by system

Find your service category

These broader collections help you browse. A category link does not confirm engine-specific compatibility.

MaintenanceBrowse the maintenance collectionBrowse category FiltersBrowse the filters collectionBrowse category FuelBrowse the fuel collectionBrowse category Ignition & electricalBrowse the ignition & electrical collectionBrowse category CoolingBrowse the cooling collectionBrowse category Belts & hosesBrowse the belts & hoses collectionBrowse category Gaskets & sealsBrowse the gaskets & seals collectionBrowse category Drive componentsBrowse the drive components collectionBrowse category

Before selecting parts

Identify the engine you have

Use the complete identification to select the correct generation, diagram and replacement part.

Mercury-built generation

The 4.5L engine is distinct from the earlier 4.3L V6 family. Current published 200 and 250 hp models do not establish one parts application for every version.

ECT & controls

Keep the complete ECT, SeaCore or control designation where present. Match fuel, exhaust, sensors and cooling components to the actual package.

Drive & transom

Identify the installed drive and transom separately. Engine, drive and transom serial numbers select different assemblies.

Earlier 4.3L carbureted, TKS, EFI and MPI V6 engines do not share a parts-fitment promise with the 4.5L family.

Send the complete engine-plate details and clear old-part photos. Match the installed fuel and cooling equipment, and include the separate drive or marine-gear plate when asking about those assemblies.

Mercury official parts catalogue Find your Mercury owner's manual

Documented installations

Boat examples

These examples describe documented engine options or installations. Boats may have been repowered or modified; an example does not establish present-day parts compatibility.

2022 Bayliner VR4 Bowrider

The builder specification lists a 4.5 MPI ECT, 200 hp Alpha One option.

Serial number help

Request a parts check

Send the Parts Desk the complete engine model and serial number, the OEM part number if known, and clear photos of the identification plate and old part. Include the installed fuel and cooling equipment when asking about those systems.

Include in your message

  • Complete engine model, suffix and serial number
  • OEM part number, if known
  • Identification-plate and old-part photos
  • Drive, transom or marine-gear identification for those parts

Parts Desk

Help before you order

Send your details through our contact page. The Parts Desk can help check the exact application before you select a replacement.

Ask the Parts Desk