Dual strut power transmission housing structure of a marine propulsion system

A marine propulsion apparatus comprising:

• an anti-ventilation plate with an upper side and a lower side, defining a thickness therebetween;
• a first strut and a second strut, each extending from a proximal end to a distal end, each of the first strut and the second strut having a leading portion, an interior belt void, and a trailing portion, wherein the first strut is aligned with the second strut and the first strut is spaced from the second strut, and the proximal ends of the first and second struts are coupled to the anti-ventilation plate;
• a lower unit coupled to the distal ends of the first strut and the second strut, the lower unit housing a sprocket therein;
• a shaft rotatably coupled to and concentric with the sprocket;
• a propeller coupled to the shaft proximate the tail portion of the lower unit, the propeller configured to rotate with the shaft;
• a belt rotatably coupling the drive shaft to the sprocket, wherein the belt is disposed within the interior belt voids of the first and second struts;
• and
• a thermal circuit channel extending through at least one of:
• i) the anti-ventilation plate,
• ii) the first strut, and
• iii) the second strut,
• wherein the thermal circuit channel is configured to channel a coolant to flow bidirectionally therethrough.