Abstract: A marine engine has first and second banks of cylinders; a supercharger configured to supply charge air for combustion in the first and second banks of cylinders; first and second charge air coolers configured to cool the charge air, wherein the first and second charge air coolers each have an upstream inlet that receives the charge air from the supercharger, a downstream outlet that discharges the charge air for combustion in the marine engine, and a bypass port for conveying a portion of the charge air, the bypass port being located downstream of the inlet and upstream of the outlet; a recirculation passage coupled to the first charge air cooler, the recirculation passage conveying the portion of the charge air from the bypass port of the first charge air cooler back to the supercharger; and a mounting plate coupled to the second charge air cooler, the mounting plate preventing flow of the portion of charge air through the bypass port of the second charge air cooler.