The C32 marine propulsion engine is available at ratings that meet IMO II emissions regulations. It has a separate circuit aftercooling system (SCAC)...

Cat C32 Propulsion Engine (US EPA Tier 3 / IMO II)

Cat C32 Propulsion Engine (US EPA Tier 4 / IMO III)

C7.1 Marine Propulsion Engine (U.S. EPA Tier 3 / IMO II)

The C9.3 ACERT propulsion engine has a B rating of 375 bhp (280 bkW) at 1800 rpm, a C rating of 416 bhp...