"MAN B&W 6S50MC-C" or "YANMAR 6EY18" sounds like a precise description. For spare parts it is only half of one.
Makers change components during a production run: a revised valve, a different bearing supplier, an updated fuel pump. They also build engines under licence in several countries, and licensees make their own modifications. The serial number tells the supplier which version is installed.
Without it, the supplier either asks and waits, or quotes the most common version and hopes. When the guess is wrong, the part arrives, does not fit, and the vessel pays twice in freight and time.
Put these on every engine requisition
- Engine model and serial number from the nameplate
- Builder or licensee
- Year of build, or the vessel's IMO number
- Any known modifications or retrofits
It takes one photo of the nameplate. It saves days.