the piston engine cooling system includes multiple pistons rotatably coupled to a crankshaft . each piston includes a piston head defining a cooling chamber therein , and a connecting rod coupled to the piston head . the connecting rod includes a connecting rod inlet channel therein allowing oil to enter the cooling chamber , and a connecting rod outlet channel receiving oil exiting the cooling chamber . the crankshaft defines a crankshaft inlet channel allowing oil to flow through the connecting rod inlet channel , and a crankshaft outlet channel receiving oil flowing through the connecting rod outlet channel .