Last winter I bought a 26 feet boat with a OM617 marined engine installed. As the boat is from 1983 I believe the engine should be the OM617 with 88 PS (87 hp/65 kW). But to be really shure, what will identify a 88 PS form a 80 PS (79 hp/59 kW)?
Most likely the engine is from after 1979 as boat built 1983.
But, a marined OM617 could (At least here in Norway) be made out of "stocked" old engine blocks.
Does the year of production bee labeled/stamped/casted into the engine somewere?